A few ways to narrow your search:
*
https://www.tnaboard.com/ -- Seattle and surrounding areas are very active, good for finding escorts and massages
*
http://www.usasexguide.nl/forum/forumdisplay.php?721-Seattle -- active discussions
*
https://rentry.co/kgirls#seattle -- some Seattle AAMP agencies
* You can also consider checking out strip clubs, some offer good mileage. Pandoras and Kittens are worth visiting