I copy/pasted this from a recent post. This is a reply that LDG gave regarding socializing an adult feral mom cat and her 4 month old kitten.
"Get a t-shirt really good and sweaty, and put it under the food dish. This will help reinforce her association of your scent with good things.
Another really good thing to do is just be in the same room with her - at her level. If you've got a laptop, or you read or sew or knit or whatever, just be in the same room - but sitting on the floor. Let her just watch you.
Interactive play can be good - though it may take a little while for her to figure out play. We found that for ferals, just a long leather bootlace with a knot tied into the end of it makes a great toy. It wiggles like a snake or a mouse tail or something, and it can be hard to resist. If you want to put a little more distance between you and her, tape it to a stick or dowel rod or something (that makes it easier to wiggle good too). Just make sure you don't leave it out anywhere she can get at it or she'll likely try to eat it.
Harp music is very calming for ferals. If you want to put on a CD and play it - even while you're not home - try this: http://harpist1.tripod.com/id32.html
(I think they ship to Canada).
You can also try Feliway spray and/or Bach's Flower Essences. She doesn't seem nervous - but they still may help. Both can be purchased here: http://www.catfaeries.com
Also, when you look at her, don't look her in the eyes. This is interpreted as a sign of aggression. Look at her forehead, or over her head. If you're in the same room with her and she can see you, close your eyes and turn your head in her direction. Cats often communicate trust with humans by a long, slow blink - so "looking" at them with your eyes closed helps promote that sense of trust.
Other things you can do - cats often yawn and love to stretch. If you're in the same room reading a book while sitting on the floor - set the book down, have a yawn (even if fake), close your eyes and have a stretch. And then just pick your book up and start reading again.
Actually, reading out loud or talking to the kitties out loud is great for them. Singing, too. You know the expression, whistle while you work? Sing while you're doing dishes or folding the laundry, or whatever.
I love the treat trail with your hand just sitting there. Do make sure it's palm down. With dogs you stretch your hand out with palm up - it is the opposite with cats. It is less threatening to them. Though apart from the treat trail with your hand down, I'd recommend avoiding reaching out to her at all (except when playing with a wand toy).
If you're sitting there reading or whatever and she does finally walk over to investigate - ignore her completely. Don't look toward her, don't reach toward her - just ignore her presence. This is the least threatening thing, and will make her bolder. The first time she may not get right up to you - but eventually curiousity will get the best of her, and she'll sniff you - and one day, I'm sure she'll headbump you.
Our advice when it comes to - especially older - ferals is to not attempt to pet them at all until you've gotten that first headbump from them.
And remember - cats are contrarians. Apart from sometimes trying to play, everything else you do to help her want your attention (sitting on the floor, etc.) is done in the context of not obviously letting her know you're doing it for her benefit. In a nutshell, the advice is to ignore her completely. Other than your regularly scheduled treat trails or attempts to engage her in play - just completely ignore her. Nothing makes a cat want attention more than being ignored. Of course with ferals it will take longer - but ignoring them and pretending they're not there does speed up that "trust" process. If you're constantly seeking her out and trying to engage in some kind of interaction, it keeps her wary - what does this person want from me? If you limit those attempts at interaction to short play sessions and your treat trails - and otherwise ignore her presence, she'll "get" that you don't want a single thing from her. And that's when you'll wake up in the middle of the night with her sleeping on your bed. Or when you'll be sitting there watching TV, and you'll feel that "bump" on your leg. Just do your best not to jump out of your skin in happiness! "
Good luck to you. I have gone through this same thing with 4 ferals living with me now. You are doing a wonderful thing for them.