Since its after the holidays I figured we need some kind of checklist for all users who are starting out with the DX (or android in general) and want to modify their phone. So without further adieu..
1) the sbf files! keep on your computer - these files are used in RSDlite to flash your phone back to stock even when you cant boot up properly
ALL SBF FILES (thanks 1KDS)
2)RSDlite 4.9 - simple google search will provide this program for windows. sbf files arent useful unless you have this.
--and of course a guide on how to use them
2.5) this for non-PC users (again, thanks 1KDS)
3) z4root - easy way to root if you have to sbf. keep on ur sdcard.
z4root download links / Get your root on here!
4) bootstrap - need an alternate recovery for nandroid backups and restores and to use the .34 files. keep on your sdcard.
(removed from his site - need to get it from the market)
5) A charged battery! any modifications that result in you having to flash the sbf - you will be STUCK if your battery isnt properly charged (50% at least) and you cant charge it when its stuck loading.
6) .apks of necessary apps (optional) i use titanium backup to restore apps after installing ROMs but if you wipe you dont have the app. just go into /data/app and copy the .apk(s) that you need and put on your sdcard for easy installation after a wipe.
Like always, neither I nor droidxforums take any responsibility to what you do to your phone.
this might be a bit much for anyone starting off with android so just take your time reading all relevant threads and feel free to ask any questions here.