UKH

I'd like to have a go at making a few bits of gear, particular a simple drybag style rucksack and a some fleece hoodie.

Can anyone recommend good resources for patterns?

Good shops for buying decent outdoor fabrics? I'm thinking polartec/pertex/cordura

Pennine Outdoor sell loads of specialist fabrics and have a lot of useful guidance on the website.  I have only ever ordered online, but I think it is possible to visit the physical premises as well.  Not sure about patterns - I've certainly just adapted street patterns for things like fleeces.

https://www.profabrics.co.uk/

https://www.stitchbackgear.com/patterns

https://learnmyog.com/alphaRaglan.html

Extrimtextil is excellent for technical fabrics, and they have just restarted shipping to the UK albeit with a minimum spend. 
For a fleece hoody/jumper I did a lot of research into patterns and found this one to be well reviewed: 

https://www.extremtextil.de/en/fleece-pullover-and-vest-pattern-gp512.html
 

it’s very similar to a Patagonia Synchilla style. I adapted the pattern slightly by making the body 5cm longer and arms 10cm longer but only found this out by making a test version with some cheapo fleece from the local fabric shop. 
 

The UK based fabric shops Pennine Outdoor and Profabric are also very good and ship quickly but tend not to have the branded cordura etc fabrics. 
 

For getting the basic bag making skills, I would highly recommend some of this guys tutorials. Helped me get up to speed with webbing, zips, templates etc

https://m.youtube.com/c/MackWorkshop

good luck, enjoy, and my top tip would be to not use your expensive fabrics on the first attempt! 

I'd second Extremtextil if you want things like polartec, pertex etc. There is a minimum order now so you'd need to buy a fair amount of fabric. May be best getting some less technical stuff first from one of the UK suppliers and seeing if it's something you like doing.

I had a go at making a fleece - copied the pattern from an existing fleece that I own (various tutorials online on how to do this - very straightforward)

Cheers folks all very useful. Is there not a UK source of branded (polartec?) Fabric?

Seems strange that the only ones I can find are abroad.