Ok, I did this and I got my plans from Popular Woodworking.
Check their website, might be able to provide a copy on line
or at least you can order up an article.
Also, check your local library (the big one in town, or the
nearest big city one). Check the stacks for woodworking,
cabinet making, etc. You might find Danny Prolux's books
which are very,very good.
Finally, just buy a good book - go to Barnes/Borders, or
better yet, your local bookseller and see what they got
on cabinet making.
I made mine out of MDF - terrible mistake - the
panels weigh a TON and they are hard to join properly
without a lot of fussing. I'd use 3/4" cabinet ply
next time - get the cheapest you can find. After all,
it's just a garage cabinet!