The path (for Win7 at least) goes "n:\Users\username\My Documents\BioWare\Mass Effect 2\Save"
And each character has it's own folder and that is setup in a particular fashion as well. It's setup as
Game Version number (without points in place)
Date created in DDMMYY fashion
And has underscores between each section. So my Soldier named Nashiri with version number 1.2 and created on May 31, 2010 has a folder named:
(So far as I know, as long as the version number and class is accurate, as long as the rest is in place, it will work.)
Finally, when you start up the game, you will have an option to change career and it should pop up.
Thanks for all the info,I found a site masseffect2saves.com I followed their instructions using their saved game and I am now playing the Arrival DLC with no problems and the trainer works great, but the doctor is not your squad member so you have to protect her,the Squad Super Health doesn't apply to her.