there's a shop at burlington plaza or something selling tubes... 2 shops there actually.. but one shop's service sucks.. and the other's not bad. basically, its hard to get good tubes coz the shop doesn't know which tubes are good for GUITAR amps, they're expertise lies in audio amplifiers. They do sell JJs, Sovteks and EHs and other expensive NOS tubes like Mullards and Telefunkens. I bought 2 JJ EL84 tubes and 4 12AX7 EH Goldpin tubes... threw away my Mesa Stock China Shuguang tubes... and I NEVER LOOKED BACK... smooth gain and excellent breakup and tube saturation. the JJ EL84s give my cleans a bell-like chime and a lot of mid-end boost. The EH preamp tubes are high-gain tubes, a little edgier and smoother. You may wana get other tube preamps that give lesser gain or wadeva.. tell me more about what kinda sound u wana achieve? basically. my mesa's turned into a rock and blues machine... just the way i like it