Mid-April going from BWI to DC, staying 2-3 days then on to Richmond...Travel solo so don't want to get into Richmond after dark. Otherwise have no restrictions.
Have only traveled by train from BWI to Philly--but have never gone south..
appreciate any advice...

There are two train stations serving Richmond.

RVM is the big old Main Street Station in downtown Richmond. You'll want to check amtrak's site but my recollection is that there are only 2 a trains day going to the Main St. Station, one arriving mid morning and one arriving late afternoon. All trains coming from DC are routinely behind schedule so the later train could get you into the station at dusk or dark. Catching a cab from the Main St. Station won't be a problem.

RVR is a smaller station with a commuter parking lot off of Staples Mill Road. All DC to Richmond trains stop there. I've only ever picked someone up from this station so I don't know about the availability of public transportation or cabs.

I've used RVR. It's located in pretty much an industrial/commercial (but not retail) area. There is some bus service on Staples Mill Rd, but not much. Taxi's have been lined up near the station whenever I've used it.

Here's a great website for finding local bus transportation all around the USA:
http://www.apta.com/links/state_local/

And here's Richmond's bus system:
http://www.ridegrtc.com

Unless your train is bound for Newport News you won't be stopping at the Main Street Station. What brings you to Richmond (if I may be so bold to ask)?

My daughter often traveled alone on Amtrak between Richmond and Philadelphia (stopping in DC) until she graduated from college last May. There are some trains that are routinely late, especially those that originate in Miami headed north. If you call customer service at the Amtrak station in Richmond (not the national 800 number), they are very friendly and helpful in recommending trains that are usually on time. However, I don't think I ever remember my daughter being over an hour late arriving at Staples Mill. On the one occasion that she came into Main Street station, I thought that the area was kind of scary after dark and there weren't many people around. I have seen cabs at the Staples Mill station and at Main Street station. Staples Mill is more convenient to the West End of Richmond and Main Street is more convenient to downtown.

going to Elderhostel program that explores the citry of Richmond.
It only lasts for 2 days and of course can only hit the high spots..I plan on staying a few extra days to re-visit some of the places . Plus anything "Civil War" is very interesting to me.
so I am sure I will find a lot to do.
Thanks to everyone for the info..