It depends what kind of music you are looking for. "Songs of Fellowship" (published by Kingsway Music) has guitar chords, and has a mixture of traditional hymns and more modern songs.

There's also: "Worship Songs & Choruses - Easy to play arrangements for keyboard and guitar" published by Kevin Mayhew Ltd., who also publish lots of other church music. info@kevinmayhew.com
This book has many of the modern "standards" such as "I lift my hands", "There is a Redeemer", "Knowing You" (i.e. Graham Kendrick,Stuart Townend, Noel Richards, Matt Redman songs).

Every year, after Spring Harvest, booklets are published with the new songs, so it's worth looking in your nearest Christian Bookshop. Those books always have the guitar chords.

For beautiful songs with a more folk/traditional feel, there's Eden's Bridge (www.edensbridge.co.uk) who have also published at least one songbook.

All the best,
- jeanie