There isn't anywhere you can download the CAA printed charts. You can download aerodrome diagrams, and instrument approach plates, from the AIS website, but to date nobody in the CAA ivory tower has felt that downloadable charts would benefit pilots...
To be fair to the CAA, I am not aware of any other European country whose official charts can be downloaded.
But what about Jepp? Don't they do something (pricey) with theirs?