I got the following at thrift stores (except when otherwise specified), and find them very helpful:
Alphabet refrigerator magnets (we have a fridge phonics by Leapfrog).
A dry erase board on an easel.
Games that teach basic skills - esp. Hi Ho Cherry O for counting skills & turn taking skills.
Super Why's ABC Letter Game. I cannot recommend this one highly enough : )
http://www.amazon.com/University-Games- ... B001SOZDFO(even tho it may have to be bought new, I considered it worthy of inclusion - we got it as a gift)
Sidewalk Chalk, crayons (gift).
An "Indoor Sandbox" (I mentioned this on the old board - cornmeal inside a box that can be used at a table indoors) (homemade & ultra-cheap)
A cash register that says the name of the number when you push the button with the number written on it (ours is a Fisher Price fun to learn)
Measuring cups - to learn beginning fractions.
Lots & Lots of books - esp. Bible story books & alphabet books.
Those were my first thoughts. I may chime in again later.