Small circulating fan to cool amps


I have two tube amps that are on a rack system with wood shelves. Because of the space requirements of all the components on the rack, there is not as much space as I'd like to see between the top of the amps and the under side of the shelve above. Although I have not had any problem to date, I'd like to make sure it stays that way. These amps do throw a fair amount of heat. Has anyone had any experience with a small fan that could be used for ventilation? I looked at Radio Shack and although they had a number of small fans, the smallest and lightest ones were 12v. I'd much prefer to run off wall current, but I don't have alot of space in which to situate the fan. Their non-battery fans were just too big and heavy. Any suggestions?
frankm1
Radio shack does have 4 1/2" 120V brushless with sleeve bearing cooling fans that work very well. Noise is 38db. Airflow is 65CFM. They are fairly quiet and move a respectable amount of air. I have a total of three wired to 1 toggle switch with a red light so I can see when their on for the audio side of my cabinet. They are mounted on the back and pull air from the front. I also have one 3 1/2" fan from Radio Shack that I wired with a thermostat from a 20" box fan to keep my DirecTV HD receiver cool. They work very nice. Catalog #: 273-241 for the 4". Cat # 273-242 for the 3". I just searched their web site and they show these.
Please note that I have these plugged in a separate wall plug from my power conditioners to prevent any AC noise.