Good Luck! I lived in DC for 10 years after growing up in New England and always had to resort to cutting up my own. I know it's all in my head but they were never the same.
Just to make you feel better, nothing similar here in NorCal either. I now go for the Santa Maria tri-tip or the ball tip which are delicious but entirely different because they are sliced rather than cubed.
I'm from Boston and no one ever knows what steak tips are around here (or anywhere outside of New England for that matter). This is a quintessential New England meal---pretty much found at every bar and grill I've ever been to (at least in the Northshore of Boston).
The closest thing you can probably find at a meat counter would be shish kabob steak. Otherwise I would just buy your favorite cut of meat, cut it up in to tips, marinate in steak sauce and grill.
Who could forget the "Steak Tips Murders" at the 99? Only in Boston! (Actually, that kind of thing could happen in Providence too).
I think it's easier to find Santa Maria Tri-Tip around here than it would be to find something labeled steak tips. But it's really just small chunks o' meat, so I'd go with Elyssa's suggestion regarding kabob meat, cut those cubes in half or thirds, and you got your steak tips.