new engine

Yeah, it hurts... I need a new engine. :( I have a 07 Dodge Ram Quad Cab STL with a 5.7L V8 Hemi. Where do I start to look? What should I keep in mind when looking at engines? Any tips/pointers are appreciated.

Looking at buying 2006 Dodge 3500 Laramie Megacab with 5.9L Cummins. Has 241,000 miles but only 60,000 on new engine. Automatic Transmission with what looks to be all the bells and whistles (Nav, moonroof, DVD). Price is just above $20,000. Is there anything I should be concerned about and/or...