Newbie here; I've tried to look through the archives and didn't find too much recent information so I'd like to ask a couple of questions regarding booking on Amtrak.

I'm booking a three-week tour of the Pacific Northwest starting the Saturday of Memorial Day weekend, 2011. The trip right now is looking like SAN - Vancouver, BC - PDX - SEA - SFO - SAN. I've signed up for AGR and have started pricing tickets.

I have a few questions about the ticketing process:

1. Is it best to book online, by phone or at the ticketing station? I read in another post that the sleeper car reservations are handled by a different agent on the phone.
2. I am hopefully booking early enough to get a good roomette, and I am looking to be on the left side of the train from SAN to Vancouver. When I ask for a sleeper, what are the best available options and the best way to convey it? I'm guessing that upper level and as far back from the engines as possible is the best situation.
3. How important is it to book tickets early for the Cascades train?
4. If I book a roomette, do I get an upgraded ticket on a regional rail line? I'll travel SAN - LAX on the Pacific Surfliner, where they don't have sleeper cars.

Any suggestions on rail passes, discounts, points buys are also welcome. The goal is to book the sleepers ASAP and some of the regionals later, but I welcome any suggestions on bookings themselves.

Thanks in advance!