Forgive me if is an extreme newb question but…
Is there any online stores/shops aside from Marketplace to buy assets for games? It seems Unreals marketplace is very small and limited. I know Unity has a shop but I’m guessing I can’t use a lot of Unity stuff in Unreal. Forgive me, I know very little about process, I only just started learning last week.
Thank you anyone that can help.
Welcome 
Take a look at:
:///
://www.blendswap/
Most of those assets are not ready for a game -> so you will have to edit them before you can use them in the engine. Also make sure to take a look at the content which you can find in the “learn” tab of the launcher 
Awesome, thanks a lot. I’m going to take a wild guess that I’ll need to learn Blender in order to get the assets ready for Unreal?
For the non FBX format models you will need to convert them to FBX, fairly simple usually if there are no issues with the mesh, just open it and export it out.
Also check the sample games/projects in the Learn tab (and marketplace tab) of the launcher, there is a lot of free content you can use in your games. 
Either blender or 3ds /maya/Cinema 4d/… -> but you are abel to import obj/fbx files directly into the engine
Mostly you just have to add a proper lightmap and probably also decrease the verts count (depending on your game ^^)
://
Edit:
@: time you were faster 
You should learn how to use a 3d editor in general and consider UE4 as the world builder.
Blender is a good option but might be a bit more than what you need so if you you want something simple as in you only need Wordpad and not Word is an interesting product.
://www.daz3d/hexagon-2-5-download-version
I took a quick look at it and has a real nice UI and work flow similar to Maya and tool selection is intuitive enough that one could figure it out easy enough.
Lacks FBX support but you can pipe to Studio an export from there. Does export and import OBJ.
Overall would make for an excellent companion if your need is to make static mesh objects.
Oh forgot to add
://www.daz3d/carrara-8-5-pro
Good price, does a lot of stuff game related, and comes with usable free content.
You actually can use Unity assets in UE4, you need to install Unity, import the Asset, and then go to the asset in the folder and find the FBX file … can then be imported in to UE4. You may need to check the licenses on the Unity Assets though … some licenses say only to be used in a Unity project.
site explains how to import from Unity to UE4: ://creategamesfromscratch.blogspot/2014/05/prototype-sci-fi-environment-import.html
site has some cool links for assets: ://creategamesfromscratch.blogspot/2014/05/next-steep-prototype-assets.html
I have also used the following sites for assets:
Arteria3D
3DModels - Textures (formerly Dexsoft Games)
And then of course the locations that the other posters mentioned.
As the other posters mentioned, you will need to learn a 3D modelling program eventually, I am still have great success with Milkshape 3D, but I am slowly teaching myself Blender.
Thank you very much everyone. Super helpful community here and glad to be apart of it.