I would suggest you have a look at the Tolarian Community College videos on YouTube. He has a video on this exact topic: https://www.youtube.com/watch?v=N1VIZylAl1w . As well as showing some really cool accessories in his various review videos. 

I can only speak for myself, but a signed or altered art copy of any of my favourite cards would mean a lot to me and be an amazing present.

booster boxes for the experienced magic player, intro pack or event decks for the inexperienced magic player

Are there any resources available online that list  some fancier/high end magic accessories like dice sets or nice boxes beyond the typical chessex sets and ultrapro satin towers?

Alternatively, what are some gifts relevant to magic that you would enjoy as a player, besides singles/sealed product?

Gifts for magic players?