@ Renuka :
1.. well u ll have to repeat that process to restore DATA , i suggest ask for the dump files of 1x or 3G and save them someplace safe, so that you can flash em via cdma workshop as and when needed.
2.. not really there are plenty of apps that you can use from market , one of em is SUPER BACKUP its small and helps to backup , sms and contacts, i have always used a rooted structure so i know that with titanium backup root and mybackup root you can do a app , call log , sms , settings, and contacts backup.
if you happen to have a nandroid backup of ur previous ROM then you can just boot into recovery and in backup and restore option and then advanced restore to , restore the data only , this will give you all ur data back.
3.. to get evdo , u need to contact the guy from whom u got this phone , he should ideally arrange for it , once evdo is activated you ll have to choose the plan and afterwards he ll send u the dump file for the 3g , which u can flash into ur phone with CDMA workshop .
otherwise contact the GURUs