Cigar City brewing is off of Dale Mabry, behind the Home Depot (turn on to Spruce St. and it will be on the left right after the HD.)
Tampa Bay Brewing Co. is in Ybor City in Centro Ybor. The best way to get there will vary but I usually do I-4 to 22nd then to 8th (I think it's 8th) and park in the parking garage. It's a two-ish block walk from the parking garage to the brewpub.
St. Somewhere is a bit further north in Tarpon Springs but you can buy their beers at the Total Wine in front of Cigar City.
Peg's Cantina is in Gulfport, the head brewer there is the assitant at Cigar City. You can take 275 south to get to Gulfport.
Again a bit north of Tampa is Dunedin Brewery, there isn't much in Dunedin as far as businesses go so if you get to the city you'll find it.
Cigar City has a nice tasting room that usually features other local breweries. Last time I was there they had on Dunedin Apricot Pale Ale. They also might have some stuff from Swamp Head in Gainesville, Lagniappe in Minneola and Peg's Cantina on tap.