The entire collection of 10 editions so far is available for $5, while individual issues are $1. All of this can be found in the Catalog section of the above link.
Topple has a wide variety of puzzles, including some logic puzzles like Nurikabe, Masyu, Hashi, etc. and many other kinds of interesting puzzles which we don't usually see here or in puzzle competitions.
I've been a contributor for some of the earlier editions, which also include contributions from Murat Can Tonta, Ashish Kumar and Walker Anderson.
The most recent one, Topple #10, features puzzles by other brilliant authors too, namely Sam Cappleman-Lynes, Freddie Hand, Chiel Beenhakkar (bakpao), David Altizio, Nityant Agarwal, Eric Fox and Jinhoo Ahn.
Volume 2 will follow a pre-order system, tentatively expect more details on that in January.
Thank you for the recommendation, Prasanna. I think he's actually said most of what there is to say. Issues can be downloaded and printed out and stapled to make a booklet, or solved mentally while viewed on the device of your choice. Please consider grabbing an issue yourself to see what we're all about. Also, please tell your friends about us; the most recent issues would make an excellent stocking stuffer or holiday activity.