hey BR12819,
i did the unofficial self-guided tour myself last year. i'd join you to do it again as it was a blast, but unfortunately, i live in Monterey.
a work trip left me with some downtime and i was able to follow Richard Gunn's trip from a few years before. it cost me less than $5 in gas (i had my own car)! the whole thing took me less than 3 hours. i wrote a little story about it which our fellow BladeRunner WEKurtz did a nice job of posting on his very nice site (sorry though - its all en Espanol):
http://brwl.blogspot.com/
(scroll down to the second article: Los Angeles. Noviembre, 2005)
traffic took a few minutes, but the locations are fairly close and i was able to enjoy the Bradbury Building LIVE - its in immaculate condition and right across the street is the Million Dollar Theater. a couple of blocks away i found free parking and being so excited to see the Bradbury Building i failed to realize i was parked facing the 2nd Street Tunnel (with that eerie green glow off the slick looking tiles).
if you can, i highly suggest the short trip to the Ennis House for which restoration of those haunting tiles (seen so often in Deckard's apartment) is in full swing. i spent about an hour walking the perimeter. unfortunately, the house was red-tagged at the time and closed to tours. but i was able to take many a photo (let me know if anyone is interested and i can email them). i even happened to talk to the neighbor - he told me how they lined the entire neightborhood - both sides of the street - with the Ennis Block tiles (you see this as Deckard drives up to his conapt in his spinner). he told me his wife invited Harrison and some of the cast in during a shooting break for beer and Gyoza!
there is a link to the original trip from the Blade Zone forum here with helpful info for planning your trip:
http://www.bladezone.com/phpBB2/viewtopic.php?t=1593
anyway, good luck to you. its a trip well-worth the time and of course its Mecca for all BR fans.