I'm a paramedic who is (hopefully) just about done with this adventure. My CPNE is this weekend (gulp).
Right off the bat, I'd suggest the following:
1. The general opinion (including mine) is to avoid the College Network. Everything you need to succeed with Excelsior can be found at... where, else, but Excelsior. TCN is *not* affiliated with Excelsior one bit, and is just another big expense.
2. How familiar are you with the nursing end of things, beyond the many hours you put into clinicals at the hospitals as an EMT through Paramedic student? There's a whole 'nuther skill set to learn that will not be spoonfed by Excelsior, so you will need to learn basic nursing skills on your own. It's not difficult, just requires extra time and practice. The Fundamentals of Nursing textbook will be your friend for this.
3. The jump from "Paramedic thinking" to "RN thinking" is a big one. You will become one with the nursing diagnosis, care planning, and such that just doesn't make a whole lot of sense to us at first. Be patient... it'll eventually hit you and you'll see why nurses do what they do in their environment.
4. I have found that the time and costs I have invested into the program are comparable to attending a brick n' mortar nursing school, with one big benefit: I can still work full time as a paramedic and bring home a paycheck. You will need to set aside a lot of studying time, if you want to be competent. There are folks who can get through this program a lot faster; can't comment beyond that as far as understanding the material though.
5. Make sure that Excelsior is accepted in the states you want to license under; not all accept this education program even though it is both regionally accredited and also by NLNAC (something not all brick n' mortar schools can boast about). State requirements are here: http://www.excelsior.edu/state-board-requirements
What would you like to know? Notice that I'm not shy on dumping information on everyone, lol!