All I can seem to find is apps that read SMS and manually entered text.
For Email there is the DriveSafe.lyxc2xae Free SMS Reader available from Google Play Store.
It can read emails, but has mixed reviews. I have never tried it so can't recommend it one way or the other.
Listen to SMS text (TXT) messages, Emails and Caller-ID while driving. Read SMS!
Listen to SMS, listen to email, listen to TXT messages. DriveSafelyxc2xae reads text messages, SMS and emails aloud and lets you respond by voice (with Pro). iSpeech Text to Speech (TTS) will speak your SMS while driving. Hands-free.
According to this resource: http://eyes-free.googlecode.com/svn/trunk/documentation/android_access/apps.html#em "K-9 Mail" is an accessible e-mail program. I have not used it so I can't vouch for its quality or suitability.
Talking Clipboard available from Google Play Store, can read everything from your clipboard, and additionally it directly reads EPUB, TXT and HTML. It even can look-up your links collected with Pocket (formerly known as "Read it Later").
Make your android device read text from any application using clipboard.
Talking Clipboard for Android is a text to speech application for Android 2.2 and higher, that can read ePub Books or any text or html files. It can also read text copied from any application, using Talking Clipboard: Read Clipboard feature available through the notification/status bar. You can also open Read It Later saved bookmarks and can read it in Talking Clipboard. Talking Clipboard can also convert any webpage article to text and can read it for you.
The Read My Email Lite application should help:
Read My Email application will read out new emails from userxe2x80x99s inbox.
This state of the art application will help users to track their emails while on the go. With simple instructions the mail account can be configured and tracked from then on. New mails will be polled every 10 minutes and will prompt the user of any new mails in their inbox.
Upon selecting the option to read the emails, the application will read aloud 10 new emails.
And there's the Read My Email Pro version with greater features:
Read My Email application will allow the users to safely keep track of their important emails while on the go.
Once configured and started, the application will read out aloud the new mails details from the inbox. The mail details includes "From", "Received on" and the "body of the email". There are various options to configure the service available with the application, like Locale for reading the email, Frequency of polling the email server, stopping the email, skip the current email, go back to previous email, configure number of new emails to read and managing various email services.
This application comes with standard email services and allows the user to add their own email services. Currently this application supports IMAP protocol.
Both applications are available from appbrain.com and Google Play Store:
I have just loaded Web Page Reader. It works great on web pages, even though Android's standard voice output is very tinny (up to Android 4.0). I loaded the Ivona voice (Amy) which is the most natural I have found, and it is brilliant. Works exceptional on the Samsung Galaxy Tab.
There's a new app out for android called AudioMail. Maybe you could give that a try.