PRO-163 is a pretty decent scanner for this area... There are digital signals out there, but there are no public safety agencies here in Western WA yet that have gone digital. The 163 will let you listen to Thurston, but also the Pierce CO trunked system depending on how far you are from Pierce CO...
There are also others out there that are less expensive that you can get that area with... If you are looking to really go inexpensive, look on amazon for a BC355C...they go for about $80 and are pretty nice for base scanning...