My two favorite resources for homeschooling, and everything else, are the internet and the library. I find both invaluable.
We have always made great use of the library. We made it a point to visit regularly. The kids would pick out books that they were interested in and I'd pick out books that I hoped they would be interested in. :) We would get books to read purely for pleasure and books that would hopefully be pleasureable as well as educational.
Unfortunately for us our small local public library became a part of the high school library and we were not comfortable in going to it during school hours. Instead we took advantage of a library in a bigger community about an hour away. We all looked forward to library day when we would pack up the van and take off for the day. We'd spend an hour or two at the library and then we'd head out to eat somewhere and then hit the stores for a little while before we'd head home. Usually the kids were busy checking out their books during the ride home.
As the children got older I discovered more and more what a great resource we had on hand in our own house with the computer and an internet connection. Through this resource we could connect with people from all over the world. We also discovered that there were lots of great learning related sites for all different subjects available through the internet and we've taken advantage of a lot of them over the years.
In my mind a library card and an internet connection are two very important and very useful resources.