Engines:
Link for prices & ordering:
http://www.jdmhondaparts.com
Options as far as motors go and what you can do with each:
B18C5- Integra Type R motor- 200hp, excellent engine for going naturally asperated. High compression, and loves to rev. Nice red valve cover too

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B18C1- Integra GS-R motor- 170hp, also good for N/A build up but also good for turbo or supercharging.
B16A2- Civic Si motor- 160hp, good for N/A and turbo/supercharging.
B18B- Integra LS motor- ???hp excellent for turbocharging. Stronger rods and low compression ratio.
Turbos:
Link for prices and ordering:
http://www.optauto.com
Greddy makes some really nice kits. So does Drag. If you know what you are doing then you may want to build your own turbo kit, other wise you should probally get a pre-packaged one.
What else EXACTLY do you want to know? Did I miss anything?