@ianmanning
I have found Saved Sellers and Saved Searches to each be a buggy mess; neither can be relied on. The discussion boards are full of complaints about users not receiving Saved Search emails, or else receiving emails from zombie searches that cannot be found or deleted. Likewise, users complain of being unable to add or delete Saved Sellers, despite being well under the limit of one hundred.
One user on the UK boards recently recommended repeatedly clicking on either the "Save this seller" or "Save this search" link until it works, but I have no idea if that will work if you are actually getting an error message because you have 100 saved searches already.
Going forward, your best bet may be to find another way to keep track of searches and sellers that you have more direct control over -- by using bookmarks of searches or sellers' "items for sale", links pasted into a file or an email, or third party automated search tools. Google "automated searches ebay" for some possible suggestions if you like getting emails when new qualifying items are listed.
