Anglesey marriage for John Thomas and Ann Roberts

[Rosezi]

Can anyone give me some good tips on searching for Anglesey ancestors. I am looking for a marriage between John Thomas and Ann Roberts. I know from the 1841 Liverpool census Ann was born in 1781 in Anglesey. On the 1841 census her eldest child Thomas was also born in Anglesey in 1809. I found an 1809 baptism for a Thomas Thomas in Beaumaris , but no sign of a marriage for his parents. It's possible they married in a another  parish. Also, if I could find their marriage I can then start searching for some siblings in Anglesey, there is a 10 year gap between Thomas and his sister Jane who was born in Liverpool in 1819. 

[Deirdre784]

There's a marriage at Llandysilio (3 miles SW of Beaumaris) on 23 Nov 1806 between John Thomas and Ann Roberts, both of the parish. Both signed with their mark.

Witnesses Simon Frazier and Griffith Williams, both also signed with their mark.

[Deirdre784]

Thomas was baptised on 21 May 1809, possible brother Edward (abode Beaumaris) on 6 Aug 1815. John a labourer on both entries.

[Rosezi]

thanks Dierdre784, for you help. I have managed to find a few other baptisms for John and Ann, in the same area, I hope it's them!