Set-up of Mac MINI

Well the used Imac I bought off of Ebay lasted about 45 days and went south on me. The people at the Apple store suspected a bad hard drive and I just did not want to spend any more money on a used machine so came home with a NEW base model Mac MINI. However it does not seem as easy to set up as my IMac was. 1st the external hard drive that I had on the old one does not seem to be recognized by the new one. 2nd I tried setting up my e-mail account with Road Runner and although I am getting mail can not seem to send it. Not at all sure why. Is there some sort of tutorial site that I can go to? Hate to be so naive but still new to Macs and just do not know where to get the correct info.