Walt12,
I just finished my very first motor swap this spring. It's not very hard at all, as a matter of fact it's easier than you would think and except for having a little help guiding the motor in/out I did everything else myself.
My suggestions are take plenty of pictures of how everything is hooked up, digital cameras are best for this as they can be downloaded to the computer and saved on a disk....make a back-up copy - learn from my mistakes! If you have a 2 car garage with one clean side to work on parts and lay them out in an orderly manner that's good. If you can afford to take your time do so, and do things right the first time. After pulling the motor out it's a good time to clean up & paint the engine compartment. HINT: get a big plastic tarp from Home Depot and lay it out on the garage floor, then drive the car over it, this way any spills will be caught and you can even use a garden hose to spray out the gunk after de-greasing. A bag of cheap kitty litter to dry up any spills helps!
I used a box of zip-lock bags to put part into after I took things off the motor, I labeled them and put them where they wouldn't get kicked around the garage. It also makes cleaning brackets and bolts easy and they don't get lost in the shuffle.
When you actually pull/drop the motor get a couple buddies to help guide it while you raise/lower it, mine came out in less than 5 minutes after everything was unbolted and the new one dropped in about a few minutes more as lining up the motor mounts took more time (don't crush any arms that way).
I don't know what your smog laws are so I can't help with that much, although in the PRK I'm sure they suck. As far as buying a GM crate motor try doing a search for Sallee Chevrolet and Pace Chevrolet, both seem reputable and have about the best prices as far as I have seen...it all depends on which motor you really want. Last time I looked the GM replacement 350/200hp motor had a 3 year 36K mile warranty even if you install it yourself and was going for about $2,000.
Here's a link to my project
383 motor swap although it's probably a little different than what you want it may help.