According to Barbara Wolff, of The Hebrew University's Albert Einstein Archives, this is not one of Einstein's identifiable quotations. (Source: paralegalpie.com http://www.paralegalpie.com/paralegalpie/2009/11/did-anybody-really-say-that.html.)
The phrase "the only source of knowledge is experience" is found in an English-language essay from 1896: "We can only be guided by what we know, and our only source of knowledge is experience" (Arthur J. Pillsbury, "The Final Word" https://books.google.com/books?id=Mw9IAQAAMAAJ&pg=PA595&dq=%22only+source", Overland Monthly, November 1896). The thought can be seen as a paraphrase of John Locke's argument from his Essay Concerning Human Understanding: "Whence has it [the Mind] all the materials of Reason and Knowledge? To this I answer, in one Word, From Experience". (Locke, An Essay Concerning Human Understanding/Book II/Chapter I, 2.)
The phrase "information is not knowledge" is also found from the nineteenth century https://books.google.com/books?id=W2oAAAAAMAAJ&pg=PA59&dq=%22information+is+not+knowledge%22.
Misattributed