How difficult is it to learn the Colle System?

I already play Semi-Slav as Black.  I read that Semi-Slav reversed is the Colle System, which is somewhat inflexible and drawish but nevertheless playable.  I am looking for a second, "surprise" opening to play as White, especially in situations when I just need a draw (e.g. I have a lead in a tournament and need a draw to get the prize).  [FYI, my primary opening as White is the Ruy Lopez]

So, is it easy to learn the Colle System, especially as I already know the Semi-Slav?  If so, what are some resources (book, CD, or otherwise) that you would recommend so I could quickly learn the Colle System?

I recommend these four books on the Colle:

Winning with the Colle System by Ken Smith and John Hall.

White Opening System combining Stonewall Attack - Colle System - Torre Attack by Andrew Soltis

The Dogs of War - Practical Play in the Colle System by Terese Hatch

The Moment of Zuke - Critical Positions and Pivotal Decisions for Colle System Players by David Rudel

There are also probably many other good books available.

Also, here's a tip.  if you ever need a draw in a tournament game, don't "play" for a draw.  Instead, play for a win, right from the get go.  If you play for a draw you will often lose the game entirely.  Play for a win and you often then have your draw.

To help learn the Colle, download a large database of master games (assuming you don't already have such a database... doesn't everyone?) and then filter all of the Colle games.  Step through these games, one move at a time, up to move 12-15 or so, to get a feel for the opening and the positions.

You probably want to play the dxc5 Colle instead of the one in which White just goes for e4.

*sigh* 

OK but I don't think OP is playing against the world's best players anyway. What matters is that it is playable even at that level. Everything else depends on the players.

I think as long as White doesn't expect to play the same moves all the time it can be ok. Otherwise it probably would just lead to bad habits.

Yes, I was referring to the line in Ree-Timman

Colle system is the key to being 1300 for the rest of your life, grow up a little bit and play 1.e4 !!!!!

This might help:

http://youtu.be/Iu4_7eF-gxg