I've created a custom provider web part that I would like use to pass multiple filter parameters to a list view web part. Is this possible?
If so, is there an example or tutorial out there that shows how to do this?
I think you are using webpart connections. If so, You cannot do this.
A webpart can only be connected to another webpart through one connection type and Each connection can have only one connection type.
So, you cannot establish two connections between same instance of Provider and Consumer webpart. However, You can connect a provider web part with two instance of same consumer webpart (if the provider expose two connections points).
A web part provider can make multiple connection points available, while a web part consumer can consume multiple provider connection points. In that case, every connection point requires a unique ID on both the consumer side and the provider side by specifying the connection point ID in the [ConnectionProvider] attribute.
A good option is to use filter values from query string.
Maybe this link from stack overflow site can help you to create multiple filter webpart
You can passing two or more filter parameter by using query string web part. This link will give you tutorial how to use query string webpart to filter list item. You can use custom control to add query string to your site url.
Hope it solve your problem.