What level is this character? Most won't take a toon below 12 and some prefer 14 for the lowest level dungeons. Pledges cannot be taken until level 45 and many of the regular pledges are being done by a high level Vet so it's scaled to VR1. While I was leveling I found the group tool decently useful but once you are even 1 level too high for the (3) dungeons of that zone level you can't use the tool until you qualify for the next higher set of (3). I'm not sure if that has changed. Also keep an eye out in zone chat for people running, I see it fairly regularly when on my alts that players are looking for more for regular dungeons. Lastly if you are a Tank or Healer it'll be FAR easier to find a group than if you are DPS.
Shadow is where the truth lies. Legerdemain - The path to Thievery