Goals from Kat Fryzer and Hayley James had put Stourbridge 2-1 up in the second half after Tamworth had gone ahead before the break. However an equaliser from the visitors took the tie into extra time, and it was Tamworth who got the decisive goal in the last few minutes to settle the game.
Tamworth will face Coundon Court in the final after they beat Stockingford in the other semi-final.
The Glassgirls finish their season with two more home games in the BCWL Division 1.
Next Sunday, 29th March, Black Country Belles are the visitors to Greenfields for a 2.00 pm kick-off.
And then on Sunday 12th April the Glassgirls will play host to Title rivals Coundon Court in what may well turn out to be a winner-takes-all showdown for the Division 1 Championship. Kick-off is again at 2.00 pm.