How do I find out if mom wanted me to have any money from the sale of the house?

You should ask to see a copy of the Trust Agreement. You should find out if the house was transferred into the trust before you passed away. This information will be critical to you determine your status and your options. You should see an estate planning and probate attorney to discuss your options.

I have no idea what "she did a trustee with my sister" means. IF Mom had no will and left property solely in her pwn name (no joint owner, no transfer on death account, not in a trust, then Mom property would be divided between her Husband, if he survives and the children.

The trust would describe the use and distribution of the assets of the trust. Therefore, you would need to read the trust document to see how the assets are to be divided.