Race scanners

Curious if anyone can recommend a decent scanner for a decent price.  Tired of renting them at the tracks due to the crazy cost, (although the season-ender at Miami last season had a deal for $20 bucks-amazing) and it would be great to own one.  Trying to choose on-line is a daunting task so if anyone has any recommendations as far as brand, etc I would surely appreciate it.  Thanks.