Mine’s a pretty sorry list. The only cool thing I can offer is that I’ve sat up on the Green Monster at Fenway twice in the last 2 years (second row last year, front row this year). Those are some awesome seats.
Current:
Camden Yards
Nationals Park
Fenway Park
SBC Park
Dodgers Stadium
PNC Park
Past:
Metrodome (for both baseball and football)
The Metrodome is an utter dump and I’m glad the Twins got a new stadium. It was like watching a game in a Ziploc bag.
Baker:
It’s been replaced. Since 2000, the Tigers have played in Comerica Park.
:dubious: The Rockies were never a minor league team. They were a brand new MLB expansion franchise when Denver was awarded the team in 1991. You would have seen the AAA Denver Bears/Zephyrs in the 1980s. (Bears from 1955-1984, Zephyrs from 1985 on.) The Zephyrs played in Denver until the Rockies’ first season in 1993, then moved to New Orleans, where they still play today.
Former stadiums I have been to:
Forbes Field and Three Rivers Stadium, both in Pittsburgh.
Mile High Stadium for a Rockies game in 1993, their first season.
Current stadium I’ve been to:
Coors Field, Denver.
Ah well, I was there in 1987. The old stadium did have an antique feel, those darned support pillars blocking views.
I haven’t been to too many:
RFK where the Nats played when they first came to DC;
Wrigley Field
Camden Yards,
Fenway, and
Nationals Park,
ETA: for minor leagues, I’ve been to a game in Woodbridge, VA for what was then the Prince William Pirates and Durham, NC.
I see I’m late to the game here, but I’ll contribute anyway.
Present
Dodger Stadium
AT&T Park
Petco Park
Angels Stadium
Chase Field (while it was still the BOB, however)
Wrigley Field
Nationals Park
Camden Yards
Progressive Field
Great American Ballpark
Past
Jack Murphy Stadium
Other
I took a tour of the original Busch Stadium in the offseason back in…I guess that would have been 1997. I’ve also stood outside of Coors Field (2005) and Kaufmann Stadium (1997) during the offseason.
Worse than that, they were a *hockey *team. 
(the former Kansas City Scouts, now the New Jersey Devils)
It would have been very hard for them to play in Mile High Stadium. 
Arlington Stadium
Ballpark in Arlington
Astrodome
MinuteMaid Park
Wrigley Field
Angels Stadium
Candlestick Park
Great American Ballpark
Turner Field
In Pawtucket? I was just there less than a month ago, as a matter of fact! Red Sox vs. Yankees, AAA edition.
Been to:
Dodgers stadium
Oakland coliseum
AT&T park
Been by, but never went unfortunately
PectoPark
Citizens bank
Nationals ballpark in D.C:smack::D:smack:
Current:
Wrigley Field
U.S. Cellular Field (Comiskey II)
Fenway Park
Old:
Busch Stadium II