I deleted a user account and its content. But my HD did not gain any space? Should I use the erase feature?

Please Help!

I just bought my first Mac and used migration assistant to transfer my files from my PC. It created a seperate user which I didnt want to do. I have since erased that user but my hard drive space did not increase (should have freeded up the 50 gigs i transfered). Any thoughts on how to get my HD space back? I selected the erase home folder.

I know now just to drag over the files I need and not to use the migration assistant.

Thanks