Satin n Lace - the pony herself is worth about $15.00, without outfit, as completed listings on eBay suggest. One listing was sold with ALL of her clothing for $29.99.
Tux n Tails - He's a pretty rare pony, and yours is in very good condition. Prices on eBay have ranged from $50 +, and one right now is up there $134.99. You could probably get more if you sold Tux n Tails with Satin n Lace as a set.
Wild Flower - the prices seem to range from $10.00 to $20.00.
Baby Starflower - prices seem to range from $6.00 to $9.00, although there are a few up there going for $12.00 and $24.00, but I don't think that's right.
Baby Sugarberry - Very rare, she's worth a lot! She can go for $60.00+. I think most of the Twice as Fancy Baby ponies are usually worth $60.00 - $75.00.
Baby Pearly - Most listings have her at $40.00, but there are a few that are around $20.00 and one around $30.00. I don't know much about these ones, but that's what a lot of past listings said.
Creamsicle the Giraffe - She seems to go for around $9.00 to $20.00.
Baby Moondancer (Pearly) - I'm not too sure about this one. One listing said about $30.00, and another was around $70.00! But another listing that sold had THREE Pearly Baby ponies and it sold for around $40.00.
Baby Firefly (Pearly) - The last few listings have ranged from $16.00, $20.00, $35.98, and $39.99. However, I paid about $7.00 for mine.
Sunny Bunch - Prices range from about $6.00 to $20.00.
Baby Dancing Butterflies - Another very rare Twice as fancy Baby. I think her average price is about $75.00. But recent eBay listings have ranged from $61.52 all the way to $255.04 (new in bag). But I believe her usual price is still $75.00. You can look around the trading post and see as well.
Dancing Butterflies - Her prices range very low to very high, going from about $5.00 all the way to $55.00, but it seems like most of them are around $20.00. So I'd say $25.00.
Sky Dancer - The last few listings have ranged from $4.00, $6.99, $17.99, and $24.99. So I'm not too sure. I would say $15.00.
Secret Beauty - Since she has her key, I think that makes her worth more. Does she have her babies too? Recent listings have sold her for $6.50 (without key), $6.50 (without key and without back), $22.06 (without key), $36.95 (with key and comb), and $49.99 (with key.)
That's all I have to say. Hopefully I was some help! Other, more experienced traders, if I'm wrong on any of these, please let me know and correct me! ^_^