First Grade Reading

Ask his teacher! She will have the best recommendations based on his reading level and can likely provide you with a big list.
Also ask the children's librarian at the public library, that's what they are there for and they love to help kids find great books.
At that age my kids really loved Frog and Toad :-)

Frog and Toad books. They are chapter books, but very short chapters and the vocabulary is 1st grade level.

One of the most overlooked resources is the town's free public library and the librarians who staff it. It sounds like you've started to check that out, but are you using the library staff personally rather than just looking around? There is usually a nice display of books anyway, and teaching a child to use the librarian as an advisor is a great way to start that relationship for later on when there are projects! There is nothing a librarian likes more than a child who loves to read and a parent who encourages it! Most libraries are part of a network of interlibrary lending too, so if your child finds a series he'd like to continue, more selections can be obtained. If your son does not have his own library card, get him one. It's a very exciting thing for a child! And it gets him in the habit of borrowing/sharing rather than expecting his family to buy things all the time.

I would focus on whatever he wants to read - don't look at the reading level or push him in any way. He needs to choose freely without an agenda. The act of reading alone is usually sufficient! Kids won't choose things that are too difficult to start with. And the librarian who gets to know your child and his abilities will be on the lookout for new things that come in that she thinks he will like. YOu can periodically take your child to a larger area library in the same network as your town library (unless you already live in a city) but even so, mix it up a little and go to a different library even if the one you have is awesome. Variety really perks up a child's interest!

My son liked reading Bernstein Bears books. He also loved non-fiction - dinosaurs, dolphins, whales, reptiles. I've heard it's very common for boys to like non-fiction. He also found the "Fly Guy" books. Those were pretty short and something he could read himself. He really loved those.

It's hard! And overwhelming! There are just so many books out there. It really helped us to look at the books on display. Our library is pretty good about changing those every so often so you see different books. We also have a great school librarian who gave our son some great ideas.

Try:

Dr. Seuss's I Can Read books
Mo Willem's books: Elephant & Piggy, Don't Let the Pigeon Drive the Bus, etc.
Sam & the Firefly
Sammy the Seal (my nephew is just starting 1st grade, and that was the first book he read to himself)

There are also lots of I Can Read books based on movies, etc.: Star Wars, superheroes, sports, etc. The quality of writing isn't necessarily stellar, but the key is to capture the child's interest. My son used to like these Spider Man books that were about the size of the Bob books and came in little packets.

Also, don't overlook books that are slightly more advanced, but that he can follow along with, as you read to him. For example:

Arnold Lobel is wonderful. Frog & Toad, Owl, Mouse Soup, everything. These also make great bedtime stories.
Also, Cynthia Rylant's Henry & Mudge books.

My daughter loved the Geronimo Stilton books. Also, both my kids loved Frog and Toad.
I'm not sure where your son is with his reading abilities, so I'm not sure exactly what to suggest to you. I have never used or read the Bob books, so I'm not sure exactly how simplistic they are, but what I remember about Dick and Jane is that they were even simpler than Frog and Toad. You mention what he likes you to read to him, so maybe you could just continue with those and ask him to read a page or a paragraph every now and again...

But books like Frog and Toad and Henry and Mudge are simple, easy reading, without lots of unfamiliar dialogue and language, but they are books with a plot/story line that kids will enjoy, that aren't so long that young kids will give up on them.

Geronimo Stilton is a little more advanced and he might not be ready yet.

Cam Jansen - readers for now, chapter books for later
Magic School Bus
Elephant & Piggy
Anything by Lillian or Russel Hoban
Oliver and Amanda Pig books (author is Van Leeuwen)
Henry & Mudge

When he's ready for chapter books, some great series that are about the same level as Magic Treehouse are:
My Weird School
Arthur Chapter Books
A to Z Mysteries
Calendar Mysteries
Katie Kazoo Switcheroo
George Brown, Class Clown
Ready Freddy
Horrible Harry
Geronimo Stilton (these are a little harder)

oh try Peggy Rathman books !!! love love love her !!! for him, try Gloria and Officer Buckle.. such a darling book.. it's about an officer and his dog (Gloria) who put on school safety meetings and turns out, Gloria, rather than office buckle is the star.. you ll love it !!! There are also different levels of the Berenstain bears.. so were good in the sense that they sometimes taught some valuable life lesson like being kind to others or about sharing..
you could also do what I did with my son which is to read a more difficult to him, you read most of a paragraph, but allow him to help you by letting him read a sentence or two as you go... a good book for that is the Cricket in Times Square.. I think kids learn just as well reading on their on but also jointly..

Good Luck

My boys were always drawn to non-fiction at that age.

His teachers and the school librarian can point you in the right direction. Our school librarians were always awesome! They knew exactly the right books for each child.

There are so many great books. Depending on what he is interested is what you should be looking for.

For my nephews is was humorous books and joke books.

His teacher should be able to recommend some good books for him. Try starfall.come as well, they have GREAT reading games and he should be able to tell if it's too easy for him.

I LOVE to take my kids to the library and let them pick things that strike their reading style. Often my 9 year old says he doesn't want a book and leaves with at least two.

My boys love sports books and history books...they are 7 and 9, just started 2nd and 4th. They have loved these books for as long as I can remember.

The library should have a nice selection of books that are within his level. Let him look through the books and see what catches his eye. If he won't do it, start picking things you know he will like and he can weed through them at home.

Comic books count too, if he is interested.

My 1st grader loves Mo Willems books (Piggy Books, Pigeon books). They're on the simple side, but they're fun to read. Also, they reinforce sight words. All of the Dr. Seuss books are good too. Again, they're simple, but reinforce sight words. When he's ready for chapter books, but with less words, try the Geronimo Stilton series.

My 6 y/o LOVES the Pete the Cat books.

Our guy loved so many! We bought him assorted grades too. We could read it to him but it would help him learn/be ready for those words in the future.

Go to the AP list site and you can get a list of all the books for his grade level and others too.

You could try a trivia book (we like Weird but True) or a joke book. The sentences and vocab will be more complex than the bob books but he won't need to have much reading comprehension to enjoy them all by himself.