LOL jayney @ the quadruple post
You can sew a fitted without a serger (serger saves time though hehe). There are plenty of free patterns online to try out before buying a pattern (if you want to buy a pattern at all -it's pretty easy to make your own once you get the hang of it). Do a search for "free diaper pattern" lol, that should give you quite a few results with step-by-step picture instructions.
Good luck! Post pics when you're done!
*If you prefer, pm me and I can send links. It's 5am and I have yet to sleep so I might not reply until this afternoon, lol*