Just found this page, may be useful: http://conlang.wikia.com/wiki/Language_tools#Dictionary
Anyway, looks like Excel can solve most of your problems! I keep all my lexicon, sample sentences and conjugation tables in Excel.
For the alphabetical sort thing, it seems that Excel does not support wildcards in custom sort orders, but you could always specify helper columns, like using LEFT([cell],1) to separate the first letter in the first column, and so on with the second, third letters (that should be enough). Then specify a custom sort order by your alphabetical sequence to sort the table by the helper columns.
Of course there are other software to use, but most do not offer so many function like Excel imo.
Edit: Just discovered some options; WeSay is quite well-rounded at first glance. I have used Lexique Pro before but I'm not really fond of it. It looks quite tidy though.