This section is a collection of links and information to various online permitting and reservations options, or information on 'offline' permitting methods, focused on Washington State.
National Parks in Washington State
National Parks Passes
All national parks offer a series of passes that apply to all National Parks; if you make more than one or two visits a year, these will often save you a significant amount of money. A list of all available passes from the National Parks Service are available here. The primary pass - the America the Beautiful Pass - which allows access to all National Parks and 'Federally operated recreation sites across the country' is available for purchase here. This will cover all of the basic Forest Service locations described below as well, at least the basic fees. Also keep in mind fee-free days.
The Forest Service has a very handy flowchart for choosing the right pass for you: Northwest Passes Flowchart.
Mt Rainier requires several types of permits for various activities and offers reservations at two inns.
One of the least-visited National Parks in the US, it's also a great bargain. Limited fees and permits, never any real competition for campsites.
As with the other parks, there are variety of affordable fees for camping and other recreation activities.
National Forest Lands in Washington State
There are many regional passes available that will dramatically save money on entrance fees to a variety of Federal Recreation sites. Use the Northwest Passes Flowchart to choose the right one for you.
Fees are very light here, you need a Northwest Forest Pass or one of the other recreation passes mentioned above. There are a few miscellaneous fees for the visitor center, and a few recreation areas that require fees. Check this page for a list of modest fees.
To cope with recent financial difficulties, Washington State now requires a Discover Pass for motor vehicle access to these areas. Costs are current $30 for an annual pass (but you'll probably pay $35). This posting on the DNR page summarizes the background.
The permits can be purchased online at http://www.discoverpass.wa.gov/ and the page includes maps of the affected areas and other useful information.
For a map of locations the Discover Pass is required, see this pdf; for a more detailed map of the NW region see this one.