Does anyone have a screenshot of the collectibles?
I've have most but still missing some and been looking for hours, so it would be nice to see what colours I'm looking for.

Well there was a golden acorn.. and one time a person next door sent me a message that said that he saw some rare collectables in my yard.. Hope this helps just keep your eyes open!

Take a look in the game files - you can see all the images from the game, including what the collectibles look like.

On PC it's probably: Program Files/Virtual Families/Images/collectables_small.png

But just for you specially, go here for what you need!

Photo - sepia toned squares
Coins - pewter shades including some green and red (copper and iron oxitdation) you can see the shapes by looking at the shadow areas for what shape something is.
Twigs - various shades of brown, some are red and some are green (these seem to be the easiest to spot)

Bugs- as out of all five games I have going I have only found one bug, a red butterfly.