My .22s- Walther P22, Colt pre-war woodsman, MKII 10" MKIII5.5"
Walther is good to put in your pocket for some informal plinking, not really a paperpuncher. Check rimfirecentral for many improvements in reliablilty.
Woodsman is accurate but is a bit pricey and really more of a collector for me.
Now, on to my favourite guns, the Clark Custom 10" is probably not what most are looking for in a "plinker" but it is unusual and very accurate. The 5.5" is probably one of the most reliable and accurate plinkers/paperpunchers out there with many aftermarket grips trigger and etc. Some don't like the appearence of the Rugers, oh well, you'll have to make up your mind on that. If you are looking for a reasonably priced plinker look for a used MKII, it may even have a trigger mod in it already, it's biggest hinderance. I found disassembly of the Rugers straightforward with the manual. The Rugers are simple and as reliable as a rock.
All the guns mentioned above(in the other posts) have earned their reputations and it is up to you to decide what feels right and what fits your budget.
The MKIIIs have been "Lawyerized" with loaded round indicators and safety locks and mag disconnects. More parts but I think it is nothing to worry about.