I have recorded some free mindfulness meditations which are available on SOUNDCLOUD 
soundcloud.com/user-196401220

Apps:
Insight Timer (loads of free guided meditations, including some of mine; search Hanni Rose Mindfulness and follow me)
Liberate Meditation-Meditation for people of colour
Headspace (free trial)
Calm (free trial)

Websites:
Bristol Wellbeing Therapies (free NHS groups) iapt-bristol.awp.nhs.uk/
What is Mindfulness? (NHS info) www.nhs.uk/conditions/stress-anxiety-depression/mindfulness/
BeMindful.co.uk (Info from Mental Health Foundation UK)
FutureLearn (offer free online Mindfulness courses, the Monash University course is excellent) www.futurelearn.com/courses/mindfulness-wellbeing-performance

Books:
Finding Peace in a Frantic World by Mark Williams
John Kabat-Zinn (wide range of books, online resources and YouTube videos)
Thich Nhat Hanh (wide range of books and teachings)

Your local Buddhist Centre will also offer a range of welcoming and accessible (and often donation based) classes.

For Mental Health Support:
MIND www.mind.org.uk/   info- 0300 123 3393 helpline- 0808 808 0330
Rethink www.rethink.org/

Bristol Mental Health Crisis Line  0300 555 0334