From Web Lite Solutions:
PDF OCR X is a simple drag-and-drop utility for Mac OS X, that converts your PDFs and images into text or searchable PDF documents. It uses advanced OCR (optical character recognition) technology to extract the text of the PDF (or image) even if that text is contained in an image. This is particularly useful for dealing with PDFs and images that were created via a Scan-to-PDF function in a scanner or photo copier. Supports over 60 languages for OCR. The OCR engine is based on Tesseract. The Community Edition supports single page PDFs (or the first page of multi-page PDFs). For multi-page PDF support you should upgrade to the Enterprise Edition.