There are a lot of free and commercial PDF magazines on the internet, with various niche and topics.  Here is a small selection of street art based magazines that are available for free download. These are good enough for you to flip through while looking for some inspirations.

Bloodwars Magazine

Very addictive, full with pictures. Issue #01 to #27. Download them all

Made in street

Available from issue #00 to #04. Download now.

Trash Magazine

Available from issue #01 to #04. Download now.

Beast

Available from issue #01 to #12. Download now.

Wallspanker Sticker-zine

Available from 01 to 04 - download the hi-res version and print them out on sticker paper. Download now.