Yes, there are many dating sites tailored exclusively for gay or lesbian adults. The most prominent and reputable site is http://www.pridedating.com/.
One can find gay Christian dating sites online. Some of the gay Christian dating sites include ones called Rainbow Christians and Gay Christian Dating.
There are dating sites exclusively for Latinos. The Latino dating sites include www.latinlovesearch.com/, www.latindate.net/ and www.latinamericancupid.com/.
There are dating sites solely for Latinos. Some dating sites exclusively for Latinos include: www.latinlovesearch.com/ and www.latinamericancupid.com/.
Most dating sites are free, but they have "premium" accounts. I don't encourage gay dating sites though because they often have a huge focus on hookups. I guess it depends more on what you want from the relationship.
Match.com was the first website to be launched exclusively as an internet dating portal in 1995.
One can apply for gay teen dating using dating sites focusing on gay relationships for younger couples. A few sites where one can find such things are bisexualmale, Dlist but one can also use normal dating sites like Match and do certain selections.
The aptly-named http://www.gay.com/ provides gay dating services without providing straight services. There are many websites that are exclusively for gay dating. Gaysinglesonline.com allows you to join a membership for free, make a profile and then start sending messages to other members.
I am not sure there are any men only dating sites. IF you mean gay/lesbian dating sites, all major dating websites have this option for you to choose on them.
Google "gay online dating" for some suggestions. NOTE: There may be adult-oriented sites among those listed.
There are many free dating sites which allow straight, gay and bi people at the same time. Gaydating is one of the few free websites which are free and are limited to gay and lesbian.
There are no good exclusively military dating sites, however some of the most popular dating sites such as Match and eHarmony offer search filters. These are often the most useful.
You should start by dating. Dating sites are good place to begin.