Hi All
Wow! Thanks everyone for replying to my post.

I have had a great response from everyone I have appraoched about providing extra training around speech and language for staff, so it is really positive that we all have the same vision in some ways!
I was able to chat to the EY sencos in my area and a lot of the things you have identified are the same kinds of things. Mainly information regarding what is 'normals' and what is not and some really practical, hands on activities to try with kids. I have heard of communicating matters, in fact I went on the training for it back in March. We have decided to focus on 'Learning Together, Working Together' from ICAN in our are. This is because we have found that, although the Communicating Matters info is very sound and useful, it is slightly too high level for some of the early years staff in our area, who have had absolutely no previous training in speech and language. The area in which I work is one of huge deprivation unfortunately.
In regards to the speech sounds, I can give you a quick 'crib sheet'!:
Plosives= p, b, t, d, k, g
Nasals= n, m, ng
Fricatives= f, v, th, s, z, sh, s (as in measure), h
Affricates= ch, j (as in juice)
Approximants= l, y, r, w
ch and j, along with r, l, y and blends (e.g. tree, spider etc) tend to come last (often not until 4 - 41/2 years or even later for ch and j. I would not tend to worry too much about these sounds when children are in pre-school.
The most important ones when kids are at pre-school age are the plosives, nasals (especially m and n) and 'easier' fricatives, which are f and s and perhaps v and z. What can be important is what children use instead of these sounds, as this can indicate whether the difficulties are indicative of delay or disorder. So training on normal speech sound development sounds like it might be useful? Where I work we do not tend to work on 'th' as it is dialect in my area for kids and parents (and some staff) to use 'f' instead.
Hope that this helps! Thanks again for all your opinions, and let me know if anything I have said doesn't make sense!