I'd probably go the enom reseller route (of course, I'm a bit biased, since I'm an enom ETP
You can get a free enom reseller account from me, or from several others floating around on the net, and possibly within this forum. This type of account will give you the ability to purchase the most common TLDs (.com, .net, .org) for $8.95 per year (there are minimal other fees as well, check out the link in my signature for a full explanation).
You can also *buy* an enom reseller account on ebay. The going rate for a $6.95 reseller account is roughly $200. So, if you were planning on buying 100 "domain-years" of registration, it would definitely be worth it to buy a $6.95 account. If you don't expect to use that much any time soon (and you've indicated you might not based on the fact that you don't want to host, or get into the business of selling domain names), it *might* not be worth it.
Now... administration... as an enom reseller, you can update domain contact info en masse. (Which I'm personally thrilled about, as I will be moving in a couple of months and will have to update the contact info on my entire stable of 126 domain names.) You can also give each individual person access to maintain their domain record, while still maintaining ultimate control over the details in the event of a problem.
You can provide hosting through enom (or through any other hosting reseller relationship you'd like), or you can choose not to provide hosting. This is entirely up to you. If you don't provide hosting, or it's done external to enom, you (or the recipient of the domain name) would just go into the management record for that individual domain and update the DNS entry to point to the correct host.
If you want to "experiment" with this, let me know, I'll set you up (for free) with an $8.95 account, and you can get in there and play around and see what you think.
<edit to add>
It's also worth noting that *you* can administer all of these domains by using a single password, while giving each of the "recipients" their own password that only works for their domain name.