it is reccomended you search these forums. i think the search button sucks, but if you scan through these pages, you'll see countless postings like yours.
You will undoubtedly want a good tripod as well. If you can afford it, go for a real fluid head (lots of recomendations on this site), your pans and tilts will thank you for it. Lots of recommedations on mics can be found here too.
I'd have to say just about the same as has already been said. When I bought my DVX100A, the very first thing I bought was a case and a UV filter. After that, I got a tripod and the fluid head. I've been using it since April and I haven't even bought any extra batteries yet...!
So, case, tripod, fluid head, and UV filter - that will get you real far - it has me.
After that, consider a good microphone or leave it to your location sound mixer dude. I bought a used AudioTechnica on Ebay for $180 - it was worth it.
Thanks for the input so far. Good to know I'm not totally off track.
How about the extended warranty? I make it a rule never to get them when purchasing lexx expensive items--but this is a bit different. Worth the extra money?
Also are there any suggestions of good and inexpensive UV filters and mics? I know there is a lot of over-priced junk out there, especially on ebay, that I want to avoid.