Upvote:2
This site has a great list of free, online newspaper archives that include coverage from 1948 Palestine. In particular, check out the link for The Jewish Press site, which has English-language content for the Palestine Post and other papers in the area. I found that a search on 'fleeing' turns up a lot of relevant content... you can quickly zero in on 1948 and easily scan the results. For example, there's a May 7, 1948 article: Arabs Flee By The Thousands
Of course, bear in mind that this is an Israeli publication, so it represents a particular perspective. But it's a great primary source, just the same.
Let us know what you find.