I know we shouldn't take firewood with us when we travel to camp. Could you help provide resources to let us know rules and regs. to collecting firewood in different areas?
The answer is very dependent on where you are going. In Oregon, there is no overall state law or regulation on collecting firewood, but different land managers (like private land, state lands, national parks or national forest) all may set their own independent rules. The best thing to do is spend a little bit of time on the internet, searching for where you are going and what the local rules might be. For instance, I poked around on the Forest Service National Forest listing for Oregon, and found that (as one example) on the Umpqua they have a nicely organized firewood page. Most sites will have information on firewood in either a camping page, or a permits page, in my experience.
In your neighboring states, i.e. see external links for Washington, Idaho, and California, the regulations will differ but the concept is the same. I'm sorry it isn't easier to list all the exact resources!