I've personally found CL to be the best way, but it takes a lot of work to weed through the shitty ads and even more to weed through shitty responses to an ad you post. But, if you're patient, it can definitely be worth it!

I've found that by ignoring all the ads that are one or two lines long I save myself a lot of bullshit: guys that only type a dozen words are the kind who want to meet up NOW and will hound you from the moment you first reply to their ad, because they're horny and just need someone to get them off right away. An ad that's actually split into paragraphs has often been written by someone who's also kinda cautious about meeting someone, and wants to trim down the number of shitty responses (same thing as before: anyone who's looking for someone to get off with RIGHT NOW doesn't want to have to read more than a dozen words in ads they're looking through!).

If no-one on your local CL is posting decent ads, write one of your own! That way you're definitely making clear what you're looking for and what you're not into. You don't need to give any/many personal details - I usually post mine with even fewer than you gave in your main post there, just "late 20s guy, white, in shape", which describes ten thousand guys in my city. There might be a lot of guys like you in your city who are doing the same thing as you: looking for a good ad from a sane guy who doesn't want to meet up immediately, and is a little cautious about the whole thing. If you spell some of that out in your ad ("Not looking to meet up right away", "I want to chat and cam verify on Skype first" and/or "I want to meet at a bar/coffee shop with zero intention of anything happening that day, to see if we get along first") you'll cut down the number of "Hey,can i suck ur cock 2nite??!" replies, and also cut out the guys who are predatory or want to rush things. You won't cut out all of them, sadly, but they're pretty easy to spot after an email or two!

Also, make your ad easy to search for. Whenever I post I use a word like "jack" in the title, then use "porn", "jerk", "JO" and "mutual" somewhere in the ad: it boosts your chances of turning up in someone else's search terms. I'd also recommend setting up a separate email address: CL does mask messages, but it's always good to be able to just delete the account if you have someone hounding you rather than trying to work out how to block their emails coming into your real address.

I've tried OKCupid, but I find it really heard to approach people on there for this kind of thing because it requires so much information to be inputted before anyone treats your profile seriously and I doubt many guys on there are expecting to be looking for that kinda thing. I've also used Grindr, but find there really aren't many guys who are just into JO there - some of them will say otherwise, but I've found that it doesn't take long into a conversation before they're asking for more to happen.

However it goes, best of luck and hopefully we'll hear a success story from you on here sooner rather than later!