How to build a speaker unit?

[JSantiago]

Here's the deal I got my dads old surround sound reciver and now I want to get 5.1 surround sound. So I decided to build my own speaker units from scratch. I'm not a complete noob with speakers the first job I had was installing car audio systems but, the speakers in those where already in a box and wired so it wasn't that complicated. Anyway, the questions are: 
1. I want to build a 3 way unit for the left an right speakers but how do I choose speaker that can all be wired togather throught a crossover or something of that nature? (I'm look at all inclosed boxes except the sub) 2. I have no ideas about the center speaker other then it's probably a midrange driver? 3. Would the rear speakers be tweaters? 4. What would make my life so much easier for the wiring can I buy stuff pre wired? 
Thanks for everyone who answers each opinion counts, Ive always dreamed of this and now it might become a reality.

[sdxadmin]

The big disadvantage with pre wired systems especially in older properties is that the rear speaker cables are too short to get the recommended speaker set up as the instructions. With some systems there may be a difference in speaker size between the front and rear speakers (more high end brands such as pioneer) but most will have four or five speakers the same size (usually wideband midrange). Would find main amp unit does not have much in the way of fault tolerance due to speaker misconnection.

[JSantiago]

Great! Thanks!

[sdxadmin]

Thanks! We're glad you're our customer!

[ABrock]

This is neat