I got stuck on my dog's tie out...
Dread Maintenance
That's an incredible way to initiate cool looping, it'll sort itself, and dread lumps and bumps are the character behind mature dreads!
Yep. I recommend wool (if you can get wool roving, you can make the wool yarn yourself and it's very soft) or hemp string.
welcome
and glad we could help ya
its all about learning from mistakes
I highly recommend Katie's extensions tutorial (just ignore the dyeing section):
http://community.livejournal.com/get_up_dread_up/5324366.html
I used this method (though I mostly crocheted the join instead of sewing) and it works great. I did this when my dreads were only 6 months or so, to extend a few super super short dreads that got that way from bad splitting & a scissor mistake! I cut most of the extensions out awhile ago and only have two left... I'll be cutting those off soon too.
I understand the reluctance to buy a weft of human hair (ethical concerns, cost etc) but it's well worth it if you want to keep the extensions in for more than a couple months and have them look at all realistic. Synthetic kanekalon hair looks & feels incredibly cheap... and it is. If you shop around, you should be able to get a full weft of human hair for about $25, which will give you lots of extensions.
Keep in mind that the extension hair will dread at a different rate than your own. Commercial human hair has been chemically treated, and tends to knot up really fast. The extensions will start out long but will shrink & tighten quickly, which adds extra weight to your dreads. That's why your own dreads have to be mature before adding extensions -- you need a solid foundation that won't unravel from all the extra weight & pulling.
Hope that helps. Hey, there's half the extensions guide written right there, I think...