Donn,
I got a few extra of the smaller float chargers like below, I don't think their Battery Tender brand but your welcome to 1 if you'd like it.
Battery Tender Junior 6V @ 0.75A - Motorcycle - Batterytender.com
Anyhow I use the Shumacher 6/12 1.5 brand below and just pick them up from Advanced Auto, I think Auto Zone carries them also but are usually more money. I think I just saw them on sale at advanced for $25 I believe.
Buy Schumacher SpeedCharge 1.5-Amp Maintainer SEM-1562A at Advance Auto Parts
They also have this one which is only 1amp and you have to select 6 or 12 volt only differences and there only like $24 regular price.
Buy Schumacher 1-Amp Trickle Charger/Maintainer MC-1 at Advance Auto Parts
I put the quick pig tails on my vehicles too, and that way if there not gonna be driven for a while I'll just plug in them to a tender and then you don't have to worry about clickety click when you do want to drive it.