I can't download Google play store app after I accidentally uninstall.

Type google in your www. In your address bar and follow download procedure!

Mate same with me, I tried to uninstall some of my google factory settings but my phone wouldn't let me so I stopped them from updating and after a while I started getting an error code 491 when I tried downloading apps from google play store. I googled 491 and found this link that showed me how to fix it, If it starts happening again then just repeat this link....CHEERS..
http://android.stackexchange.com/questions/83432/downloading-from-play-store-gives-error-491

Tablet Reset

you can not download google play store app because google app store application have different extension then iphone apple app store for google app store application extension : .apk for iphone app store entension : .ipa so you cannot download a apple store app on i devices

When you uninstall updates to Google Play Store you are actually uninstalling updates to the Google Play Store app itself and not your other installed applications and their settings what you're actually doing is downgrading the Google Play app itself to the version that came shipped on your nook HD Plus. I know this Uninstall Updates wording tends to freak a lot of folks out because they think it means all updates to everything. In the app itself sometimes this is necessary if a bug is introduced into the most recent version of the Google Play app. Don't worry over time the Google Play app itself will automatically update itself again. If newer versions still have a bug on your system just uninstall updates again until they get it fixed. Over the last two and a half weeks a minor bug was discovered in Google Play that the very second you entered an apps description page Google Play would immediately stop responding to the system and crash. I sent a blind email to a Google support email address I hoped could forward it to the Google Play staff. I sent the email in about this problem about a week ago. It least on my Nook HD plus for the past two and a half days this problem seem to have corrected itself. Knock on wood.

You are the second question in a week about this very same problem between the Google Play Store app and Nooks. Hope this answers both questions and provides a solid workaround should Google Play Store ever get buggy again in the future.

Try to uninstall updates of play store.. Settings>apps>Google play store>uninstall updates..

Try downloading games and apps from Play Store and not from Google Play. Me myself, I like Play Store, because you can see it download and when it is ready it gives option to Open or Uninstall.

Try going Settings>Accounts>Google> Tap your account> Three dots in the upper right (or press menu button) "Remove Account" ... then read your account .. then if you want, clear Play store cache and data and try it

Even still to this day, it happens.
I've figured a temporary solution to fix this issue.

1. Go to settings > apps > manage apps and make sure you are under all apps tab.
2. Find Google play store and force close it. Then select uninstall updates.
3. Go back and scroll down to find Market Updater?... I think is what it is called and select force close.

From now on, only use the Market. The Google Play Store icon may disappear from the apps/app drawer... which is exactly what you want.

Problem solved.

If it ever happens again and Play Store comes up again, just repeat the process. As I said, I believe this fix is only TEMPORARY.