If you come by a selection of used charts (Imray & Admiralty) is there a web site you can go to acquire all the updates that may have been published over the years?
You can get corrections to Admiralty for the last 18 months or so at http://www.ukho.gov.uk/notices_to_mariners.html . They come either in smallcraft versions, published in three monthly blocks, or the full version as weekly blocks. The weekly ones have to be downloaded one week at a time, which is a bit tedious. there is also an index indicating all corrections for each chart in the last two years, except where a new edition of a chart has been published.