I got into iRacing a little less than a month ago and I wasn't all that into oval racing at all. I thought that since I had put a lot of time behind a wheel in GT5 that it would be easy for me to get behind an iRacing car and drive competitively. Like you I had a rude awakening...spinning out all the time and just a miserable introduction to what racing really is. I got frustrated, but kept at it and finally got to where I could finish races with minimal incidents, mostly a couple off tracks.
Then about 3 weeks in, I was sitting on my couch youtubing some videos and was looking for a fast lap around a track in the skippy as I was about to purchase the car.
Stumbled upon this video:
http://www.youtube.com/watch?v=xQRmYMlmdqM
After watching that video, it's old and an hour and a half long, the game and car physics and mechanics just made sense. I was nearly unable to drive a lap in the SPEC ford racer before watching the video, after watching...I was able to turn repeatable consistent laps. No joke! The sim just made sense. It made me realize the cartoonism that GT5 added to racing and really made me enjoy iRacing that much more. Since watching that video I have added 3 road wins and 6 oval wins to my name and promoted out of rookie to D class in both road and oval.
Good luck to you in your decision to move forward. Hopefully this helps you as it did me. I look forward to racing with you soon.