Duplicate URLs and duplicate titles

Hi I have finished my website and now that I am optimizing my site for search engines and I seem to be having a problem with duplicate content and urls I have over 1000 products which is leading to around 6000 duplicates entries.

The url should be shown like this:
www.mysite.co.uk/all-products/Product/32...core-bodywarmer.html

but under some menus the url is shown like:
www.mysite.co.uk/bestsellers/Product/329...core-bodywarmer.html
and
www.mysite.co.uk/component/hikashop/Prod...core-bodywarmer.html

I know that Joomla has different ways to point at things, but there must be a way to make the urls the same for all the products.

we can change via it redj addons, but there is not tutorial on how we can use it for Hikashop.
Or we could we use the .htaccess
But the problem then arises that google still sees the duplicate urls on the page. And we are using the server to change things.

After analysing my page at seomoz I get the following

Thanks Nicolas I have done that.

I have also configured redj for 301 redirects and left that there to pick up anything that is errant.

for anyone out that there that needs to configure redj then here is the syntax for hikashop if you have seo enabled in joomla and the hikashop seo.

In Hikashop SEO I have:

category sef: Departments.
products sef: products.

I ended up having various menus so these are the rules I created in ReDJ

from: ^/bestsellers/Product/
to: myurl.com/all-products/Product/{pathltrim /bestsellers/Product/}{queryfull}

from: ^/component/hikashop/Product/
to: myurl.com/all-products/Product/{pathltrim /component/hikashop/Product/}{queryfull}

from: ^/departments/Product/*
to: myurl.com/all-products/Product/{pathltrim /departments/Product/}{queryfull}

Thanks

Nav