J.M.
Just to add to what others have said - it doesn't matter what you paid for it new. It's no longer new. The buyer knows that you want to be rid of it, or you wouldn't be having a garage sale. People go to garage sales with little money hoping for a great find. You can try selling the nicer/bigger things on craigslist first, but to my mind, that's pretty much an online garage sale. I wouldn't ask for more than $50 for the changing table and $50 for the crib (and I'd probably make a deal if someone would take both). Clothes I would sell as a lot (3-6 months, etc) and wouldn't charge more than $1/piece.
Don't think of it as recouping what you've paid; think of it as you paid for the use, and now that you're selling it to someone else you're getting a bonus! It makes going with lower prices easier. Good luck.