Grace Church in Tianmu has English services at 9 am. Mingde MRT stop--turn left onto Mingde Rd. when you come out of the station and walk until you see the Wellcome store on the left. The English church meets on B2 (Chinese church on first level).
Grace Baptist near Tai-Da also has English and bilingual services.
The Pearl has English services: http://www.thepearlintaipei.com/
Huaining Baptist Church on Huaining Jie will be starting English services on Sunday afternoons in the New Year.
There are more--that's just off the top of my head right now.