Again the find feature didn't help me. Sorry...but when do i have the ability to warp to each city, and how so?? I visited all three cities however i just finished the hospitall assassination in acre. Im on memory block 3, and i still have to kill Tallal in jerusalem. So how do i travel between cities??

IIRC when you complete the assassination and return to the bureau leader, Altair will rest and then you'll get the option of "fast travel" back to Masyaf, direct to one of the other cities or return to the bureau so you can travel normally.

once you finish block 3 you should be able to travel between cities. you have to exit the city(out the walls and up teh trail) to have the prompt appear

i heard in the directors cut altair has the ability to jump from city to city