You can check out The Tube Store, or Vacuumetube.com - both have a pretty extensive line of tubes (some NOS stuff as well).
JJ's are good tubes, I've used the EL34 and EL84 power tubes and have been very happy with the results, I also like the Svetlana EL34's, EH EL34's and EL84's. Groove tubes has been improving thier products over the last couple of years - they're more expensive than other new tube makers. I also like the JJ ECC83 and ECC82 preamp tubes. What type of tubes are you using?