I have two of these leather harnesses for Roxie, a pink one and a shiny aqua one. They are incredibly easy to use with just the velcro fastener. I ordered the first one online, but then found a local specialty pet shop that actually sells them, so I bought a second one.
Dog Walking Harness - Safety Leather Harnesses, Pink Harness, Pet, Large, Small, Teacup, Designer
As for her collar; she has a few of the regular nylon collars from Petsmart. She wears it all the time with her name/info tag and her rabies tag. I worry that someday she'll get out, so I make sure she has it on all the time. I also like that I know where she is by the jingling of her tags. I always wash it well with antibacterial soap when I bathe her.