I saw Reptile Depot at the NARBC show in October. For a "pet shop", they seem to have a really good selection and appear to know what they are doing. I wouldn't have a problem buying from them, as long as the price wasn't ridiculous.
As for the UTH, good choice, but you MUST also have a digital thermometer with a probe so you can accurately measure the high temp right on the glass over the center of the UTH, under the substrate. You will also need a thermostat or rheostat (lamp dimmer) to control the temp as they are always far too hot without something to regulate the heat output.
Thermostat is best, for a low end but reliable model check out the ZooMed 500R ($22 plus shipping at various online vendors). A rheostat would be a lot cheaper, about $9 for a lamp dimmer at WalMart, but you will have to check it frequently and adjust as needed.