Blocking out the basic pilgrim's path to reliable colour management:

1) decent monitor, with some way of getting a good calibrated gamma (even ol' Adobe Gamma will work)
2) Deciding on an RGB workspace that you use for all apps -- there's literally libraries of debates on this one, but I'd say it narrows down to a few standard choices: ColorMatch, Adobe RGB, sRGB-- they all have different gamut ranges, but 95%+ of most sits in the 'middle' anyhow, and stuff that doesn't -- you have to hand tweak the optimization for regardless.
3) Setting up some customized CMYK profiles. Like Dan Margulis (one of the leading, if not the greatest gurus in this area), I don't see the advantage in expensive colour calibration hardware, for most people outside of actual press-side workers. There are simply too many variables to accomodate. Dan has some terrific 'generalized conditions' CMYK curves that I've been using with great success for a few years now.
4) Buy Dan's Book: 'Professional Photoshop-- the Classic Guide to Color Correction'. Dan's experience is so vast, and so firmly rooted in the empirical, that this book is like taking 25 colour courses at once. Only less confusing. After two years, I still go back to it almost daily for advice. Even if you can only afford a used version (I've got v.4) it won't make much difference because Dan goes into the whole topic in a way that defies the bulk of the other so-called colour gurus out there. And it's filled with actual test photos and such that you can actually examine to see how things all work.
5) Prayer. Even with everything else going for you, it can't hurt.

All facetiousness aside, one of the big decisions that has to be made is how you handle colour profiling on HANDOFF. Internally, as you've already noted-- it's no big deal. But when you hand something off, you have to be sure that whatever colour decisions you've made to the work are going to make it to paper. That's why, again, like Dan, I advocate that in CMYK work, you only handover CMYK files without any embedded profiles. Learn to trust the numbers and know what they're telling you. RGB? In a perfect world, LAB for RGB. In our world, LAB with instructions or RGB with profile, instructions, and a bottle of good scotch (for yourself).

typically when sending off to printing... it's not needed. alot of printers will tell you NOT to assign one. but if you have doubts..call and ask.

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>>typically when sending off to printing... it's not needed<<

Read, 'Totally ignored anyways'. I prefer to nail things down and let them know I don't want them monkeying with my numbers. Otherwise, you just end up chasing your tail-- something that's become so easy to do in colour management work.