J.,
I am a LD 8th grade special education teacher. I would try to tap into some of your son's other intelligences. Try reading and implement some of Howard Gardner's Multiple Intelligences. You can find a lot of information on the internet or in the library or bookstore. Some students just need some differentiated instruction into an area that they are interested in. Hopefully after reading and possibly taking a MI inventory for yourself and your son, you can find out what your son likes and tap into that intelligence and how to use it to your advantage.
If your son is just diagnosed with LD th epublic schools offer the best resources. You may also want to try Sylvan learning center. I have heard that they can work wonders. If it comes out that your son has another type of disability then I would contact the school about different programs that are available you probably will need to contact the administration building as that type of information is beyond what a particular school would have.
Your son is young so he was probably just tested by the school for special education services. I would request a meeting with his case manager and ask what tests where administered when and if there are any other tests available. Most of the time all tests are not used to find a student elgible for services.
And lastly, make sure you know your rights. If you don't have a current parental rights booklet get one before going into any meeting with school personnel. There are many services availabe but parents don't know about them and sped teachers aren't allowed to mention them. the school district can be made responsible to pay for a lot of the testing that you want done.
Good Luck and if you need any other help please feel free to email me.