Interesting discussions - I've only just revisited this thread so here's my catch-up 5p's worth.

Girls in Rock 'n' Roll - Alec's assessment is right (i.e. being a female R 'n' R star wasn't considered the right wholesome image for a young woman at the time). It was similar in the USA, with Wanda Jackson being very much an exception in the mid/late 50s. Most girl singers of the Helen Shapiro ilk were the female equivalent of the 'teenage idol' type of male singer that was still popular until being swept out of fashion by the Beatles and the 'beat boom' (see below). This continued to some extent for female singers even after that (big 1960s female stars like Cilla Black, Sandie Shaw, etc., were not really R 'n' R singers).

I'm surprised no-one followed up Manfred's mention of The Springfields, who were more folky than most bands in those days. They consisted of a trio with Dusty & Tom Springfield and Tim Field (later replaced by Mike Hurst). They had a few hits in the UK including Island of Dreams & Say I Won't Be There, and issued some albums with a lot of folk songs on. Of course Dusty went on to be a much bigger star on her own. As others said, Lulu didn't arrive until 1964 (initially with her then obligatory band 'The Luvvers') when the 'beat boom' was well under way (see below).

British R & R bands: apart from Clif & The Shadows and Johnny Kidd & The Pirates, there were few successful bands as opposed to solo singers, until the Beatles came along. Yes, Billy Fury had various backing groups at different times including the Tornados, the Outlaws and the Blue Flames (featuring Georgie Fame on keyboards - of course he & the Blue Flames had great success in their own right after moving on from Billy.)

When the Beatles came along, suddenly the charts were full of groups, notably from Merseyside, Manchester and London (among other places), and solo male singers were seen as somewhat old hat. The record companies tried to bring their singers up to date by finding backing groups for them, e.g. Adam Faith & The Roulettes, Billy Fury & The Outlaws. It worked for a while, until the beat boom moved on and some of these artists faded away (e.g. Adam Faith didn't have much success after the mid-1960s).