Hi Emgee,
The registers for Holy Trinity Catholic Church at Bilston are held at the Diocesan Archives, St Chad's, Birmingham. I think there may also be a copy of the films at Wolverhampton Archives.
Catholic baptismal records do note date of birth and mother's maiden name as well as godparents, so can be very useful for finding additional details.
I am currently trying to transcribe the baptismal index into an Access database but so far I have done "A"s and most of the "B"s so it will be a long time before I get to "W". Mean-time, if I do come across any Welsh/Walsh/Welch records I will try to remember to let you know.
Sheila