Husband's 40Th

Entertainment and/or DJ would be fun...try doing a theme - casino nite, mexican fiesta, hawaain luau...etc. and cook the food according to the theme.

I second the theme idea. also, you could do your best to make it a surprise. Get a goofy hat for the guest of honor (in theme of course). Oriental Trading has tons of great theme decorations and such.

We are backyard BBQers ourselves, and we did a Hawaiian Luau theme for my daughter's first birthday a few years ago. It was low-key, easy, and inexpensive but fun, and you can get good supplies from Oriental Trading Co or Party City. I bought a box of leis from Party City and gave them to guests as they arrived. The invites were postcards with the party info and Hawaiian themed stickers along the sides-- you could include a request that everyone wear their Hawaiian shirts or vacation garb on the invites. We had pineapple upside-down cake, chicken kabobs with pineapple on the grill, Hawaiian baked beans-- if you search Recipezaar.com you can come up with a menu tailored to your budget, tastes, etc. I gave the kids inflatable toys from Party City (they had a whole luau section with inflatable palm trees and all that). We had a great time and it was very low-key and casual.
Good luck! Being a hostess does not come easily to me, but I love thinking up themes for other people's parties!

Depending on your budget, catering a BBQ can be an elegant affair. My brother did my other brother's rehearsal dinner in July in his yard. He bought a big backyard tent (can rent) and had round tables w/ white tablecloths & a fancy looking table set up. He hired a rather gourmet BBQ staff. This was in NY and I don't know his budget, but it was really nice. I do know an excellent band for hire if you like contemporary, dance type music. They're weekend musicians but they're so good. Don't know what they charge. I think they have a website: Soul Provider is their name. They do lots of home parties. I've been to surprise parties at VFW or American Legion Halls that aren't fancy, but it kept it secret and no need to clean your house! Some catered, others potluck. Those were the better food.

Casino night souns like a good idea! as well as renting the round tables..They add a nice look to the back yard, I have done that before for my Grandmother's surprisse bday party in the back yard and i purchased a nice Tent on sale a target to put the food under (buffet style).

My Table and chairs guy is Blair @ ###-###-####( he is awsome) and he will drop off and pick up(on Sundays)and inexspensive.