It is no secret that babies don't need a lot of toys. In fact, you may already own many of these items.
0-6 Months:
Something easy to hold, transfer between hands and chew on. We have these rings. I think they only cost a few dollars in the store. Handy for keeping track of toys in the stroller as well. Just hook them to the toy and to the stroller and you'll never be picking up a toy off the dirty ground. Perfect for two tiny hands to hold and chew on.
Something to bang together. Anything will work but I like these blocks. Good for later use as well. These cost about $6 in a store. Can you believe the prices online?! Of course, you can bang lots of household items together as well. Measuring spoons are always a hit.
Something to chew and suck on. A wet wash cloth is great for this. Teethers are also good.
A mirror. You can hold her up in front of the bathroom mirror or buy a special baby mirror she can hold and look at. We have this one and have gotten our money's worth.
A jumper. My kids all loved these. Any toy that holds them in an upright position seems to be a pretty big hit with the 3 to 6 month crowd.
6-9 Months
Play silks. From peek-a-boo to covering baby's head to stuffing them in an empty kleenex box for baby to empty they are one of my favorite baby toys. Maggie goes nuts over these. I bought a bunch for around $2 a piece online with the intent to dye them colors but I rather like them plain.
Something to shake. Like this, or possibly this. Or really, fill an old plastic easter egg with rice or beans and hot glue it shut.
A ball. It rolls. Babies this age love to roll the ball back and forth to you- or try at least.
Different textures. You can buy fancy texture toys or special texture books or just fill a plastic bowl of different textured (safe) things you have around the house.
Cause and effect toys. There are tons of toys out there that fit this bill. Anything where you push a button or slide a lever and something happens. Not necessarily battery operated. You can probably find something in your house to fit this bill as well. Obviously a ball is cause and effect. The DVD player buttons are cause and effect as well. Pulling mom's hair is a good one.
A stuffed animal. Not all kids even pay any attention to them at this age but I like to keep them around. They are soft and snugly and cute.
A play table. All babies are different but sometime around this age babies can hold their weight on their own legs and love standing and playing. There are all types of tables from wooden ones to lego building ones to plastic noisy ones. Just make sure it is age appropriate (no babies this age can do legos or these) and sturdy. I've been to many play areas with unstable wooden play tables. We have this one and even though it is noisy, everyone loves it.
A box or a bowl. Fill it full of fun little things to dump out. Endless fun.
9 to 12 months
A "baby". I love to see the look on a baby's face when they see a baby doll. Such joy.
Musical toys. Pots and wooden spoons or real toys, whatever. Babies love making noise.
Shape sorters. While we have this one (remember it is only $6, not $59), the 3 ball tennis can is our favorite first shape sorter. Of course, they all fit in the hole. This is actually something this age group can accomplish. The other shape sorters are fun toys but most babies can't actually get the shapes in the holes themselves.
Nesting blocks or cups or stacking rings. Good for stacking and destroying as well as banging together or nesting. Plastic measuring cups can work well for nesting. They are also a good bath toy.
A kitchen drawer. All those great plastic bowls and lids and wooden spoons and measuring cups can keep a baby entertained for a while.
A push toy. Doesn't have to be fancy, just stable. Of course, not all babies this age will be able to do this but you can always help them. They will love it.
A ride on toy. This may be a bit advanced for some babies but my oldest played on this bouncing pony from ten months on. A definite favorite in our house. Hours and hours of riding the range.
Of course, there are tons of other great toys out there you can clutter your house with, and I have my house cluttered with, but I think this is a pretty good list of toys that are really nice to have. What would you add or subtract?