LOL Shawn
All this information and more is gonna drive ya up a tree...

You have asked a question will return a thousand suggestions and opinions.
What I have always heard is this..
What do you want to do with the air gun?
Do you want to plink?
Do you want to do small game hunting?
Do you want to compete?
Airgunner is correct. The Co 2 will be worthless in the winter months.
A decent Springer will give you constant velocity all year round.
A PCP will also give you constant velocities all year round. "High Pressure Air" (This statement is based on what I have read)
PCP's are more expensive normally to set up than Springers or Co 2 air guns.
You can buy a good Co 2 from Mike and it will work fantastic in the warm weather.
You can also buy a good Springer and it will work very well all year round.
There are literally hundreds of air guns out there. And one heck of allot of good ones. And allot of junk to:)
Basically you want one that shoots above 700 FPS for a 100 foot shot. That's for killing squirrels and small rodents. My Opinion:)
I have only been in this sport for 6 to 7 months. My love for the sport has lead me to creating this forum, just for people like you Shawn, that have never really owned an air gun but has the interest and desire to enter the sport. We have a great bunch of experienced air gunners here in this forum and you will find that they know what they are talkin about. We have also put a library section here so new and fermented air gunners can read articles on tuning, design, schematics, articles etc.
Now back to the original question....

What do you want to do with your air gun??
Just read posts to get an idea of what air guns can do and ask lots of questions

Gene