Bibles come in different translations, include different notes, and come from different publishers. Here are some things to keep in mind when purchasing a bible:
The translation used by Catholics at Mass is the New American Bible Revised Edition (NABRE). Another good translation is the Revised Standard Version (RSV). Look for these translations when purchasing a bible.
Study Editions will include more notes and information about the text. Reader Editions will include less information, but can be more enjoyable to read.
Publishers will use the same translation of the Bible, but include different commentary. Reading more about an edition of the Bible before you buy it can help you find a bible that suites your needs.