Re: Building a effects rack...
I don't really know your situation, but you might have a job using it live unless you are fully in control of the sound (rather than a venue with its own sound gear).
Also like another poster said, this is perhaps all a bit old hat:
I used to do sound for bands and used an analog mixer with all outboard gear. Now I have a digital mixer (Allen & Heath QU-16, 16 mono channels, 3 stereo = 22 channels) I would never go back.. it's just so much easier. All the compressors, gates and FX are built in, and you have 10 flippin' aux buses!! Couple that with powered FOH speakers and powered wedge monitors and it's all so easy. On top of that, you can save "scenes", so you can recall your exact settings from any gig (this is priceless if gigging a lot, so much time saved).
Basically, if I am doing the sound with my rig, I have the QU-16 next to me and put the entire band through it. From there I can mix the monitors during sound check / performance. I use an iPad out front to set the sound up (it talks to the QU-16). Then I give the iPad to someone who understands sound, and play the gig.
People can also mix their own monitors using their phone..
PLUS you can multitrack record 18 channels onto an external HD (you literally just plug a HD into the mixer, or even a USB stick at a pinch but it doesn't work quite as well). AND you can use the mixer as an external sound interface for your laptop.
If I am not in control of the sound, I just let the venue sound people deal with it and forget about sound. It's much more relaxing that way.
I was very reluctant to go digital, but am very glad I did. It's not expensive either.. And the cheaper Behringer board someone else mentioned is also very good from what I hear.
Photos from a recent Wedding gig.. no racks or amps in site, nice clean easy set up, just 1 mixer on a table next to my drums (you can just see it in the first photo), running 18 channels for the band and 4 monitor mixes (3 wedges, 1 stereo IEM) : -
(And yes I am ashamed I forgot to replace the clear bass drum head! It looks messy)
EDIT: There is one down side to all of this: single point of failure. If the mixer goes, I'm screwed. However, I do carry a little Zed 100 analog mixer with me that I can stick the money channels through (vocals) if needed. For the price of the Behringer XR18 though it's probably worth picking one up as a back up / second mixer. It's all much easier and cheaper these days.