If you are Alliance there are two routes excluding a hearth out. You can go to Paw'don Village in the Jade Forest and there will be a portal back to town. Since you are 87 you can also go to Kun-Lai Summit and do the Anduin quest chain (again speaking from the Alliance point of view, not sure how it is for the Horde). Once you finish the stuff in the Temple of the White Tiger you will be sent to just outside the gate to the Vale of Eternal Blossoms. After that head to the Alliance base in the southeast corner of the zone and BAM, portals to all the other major cities. It should also be noted that you will be safe in the Vale if you go east. Go west and you will encounter 90 mobs with 500k hp.
Well use your hearth stone if you have one. and if you don't go to pawdon village and use the port! Or you can contact a GM and they usually reply fast to stuff like this.
I was stuck in the middle of the outlands and had no hearth stone so i contacted a GM and told him i was "really lost"(even though i wasnt. i was just to damn lazy to walk 10-15mins to get back! so he teleported me to Shattrath and i went off from there.
Thanks for all of the good advice. Somehow I missed seeing the portal when I got to the first zone. Since I was already 87, though, I went to the white tiger temple place, did the four-part quest, and was able to go to the new capital. Now I have portals galore, trainers, etc.