selenium to read text contained in tile image and click on a button [migrated]

selenium to read text contained in tile image and click on a button
[migrated]

I have a web page with contents like tile images which includes some text
content and an image in it. In my application user will enter a text in a
text box. What I want to do using selenium is that I want the text to be
read somehow which is displayed in that tile image and if it match with
the user entered text then I need to click on the button displayed below.
Since I dont have enough reputation, I can't post a sample pic showing how
the tile and button look like.Sorry..
The tile image text has got same "classname" for all tile images and the
button has got unique id's. But since I cant predict user entered text, I
cant use ID in my application.
For your understanding, I am posting html code for both.
HTML Code for tile image text:
<span class="rm-displayBlock rm-marginBottom5px rm-fontWeightBold
largeTileTitle rm-textOverflowEllipsed">10monkeys.com Maths (FULL)</span>
HTML Code for Button:
<a href="JavaScript:;" appid="f03a1962-38fc-e1f5-cee1-a8a9ce4684a5"
id="d70e5839-a9cd-b86f-cba5-3c41cd0826fe" class="btn btn-primary
rm-floatLeft">Buy</a>
How can I achieve What I said? Any comments would be really appreciated..