EQ and compressors are tools with many applicaitons - they aren't "meant" to be used in as narrow a capacity as you have in mind. The basic model for making a recording involves three phases - tracking, mixing, and mastering.
Tracking - Recording the original performances and overdubs - effects are typically used conservatively here - you can always add more compression, eq, etc, later, but you can't take it away. Therefore, the most sensible philosophy at this stage is to only use eq if there's a really offensive component of what you're recording that you absolutely will not want. In digital land, light compression is often used to improve resolution - I don't know how this concept translates to analog-land, but avoiding effects at this stage is the safest route.
Mixing - use levels, panning and effects to get a good balance here. This is where you'll want to apply eq to a) get rid of remaining offensive components and b) make cosmetic changes to tone. Compressors are remarkably versatile, yet challenging to master. Search the forums and the web in general for their many applications - the most basic of which is to bring a track with too great of fluctuation in volume to a more usable, standard range. I must say, I don't envy your analog setup at all (I love my PC-based DAW), and its because of this part of the process. If you want to apply one of these effects to multiple tracks, and you only have one of each, you've got to do it one track at a time, bouncing from your original, through the unit, to a new (unused) track. This limits the number of tracks you have to work with AND is destructive (you introduce a little distortion every time you send it through an effect).
Mastering - once you're happy with your mix, you send it off to get mastered. Or, if you're like a lot of us here, you master it yourself. This is where you apply effects to the final, stereo mix. The primary (though debatably wise) goal of many recordists is to get the volume up to commercial standards using compressors/limiters. Of course, this too is a very deep topic to which many forums, threads and books are dedicated.
