I have quite a few clothes and some other items I would like to donate to charity. However, I do not have a car, so it is difficult to transport these items. Is there a charity that will come by the house to pick up items?
The only pick up I know of for clothes and shoes are the Texaid/Caritas charity collections 2 or 3 times per year. You normally get a bag in the post box with a pick up date printed on them. Just fill the bag and leave it outside early on the day of pick up.
You could ask around on the day you receive the bags if any of your neighbours don't need them (or I just nick the ones that are delivered to our office, for example) if you have more than one bagful of clothes.
There are loads of the clothes collection bins dotted around all over the place so it should be fairly easy to put a few things in a bag every time the OP goes out and dump them in the nearest bin. Unless the OP has mountains of stuff it shouldn't take many trips.
Many brocki hauses will come and pick up if you have a lot of stuff. I've had the one on alstetten come to pick up things from my flat. I believe it's called Arche.
you might also consider advertising the items as "For free, collect only" on this forum, or on fleedoo, tutti and anibis.
Sometimes, churches collect goods to send to wherever they have a charity or mission station going: you could enquire at churches near you.
You could ask at the second-hand shops, (called "Brockenhaus"), but you'd best check with them first, as some may collect for free if you have enough goods or if you are very near them, whereas others charge you a fee to do this service for you.
If you find one, they might charge you a fee because some people thinks donating garbage is "charity".
Clothes are fairly easy to transport with a borrowed shopping cart or a trolley, you can get them to the nearest container.
As for the other items, think it through whether they are of any value (specifically, more than the transportation costs to the end user). If not for charity try second hand shops.