Add
tblUSBDevices to your report, then pick the fields from that table that you want to see. E.g.
Select Top 1000000 tblAssets.AssetID,
tblAssets.AssetName,
tsysAssetTypes.AssetTypename,
tsysAssetTypes.AssetTypeIcon10 As icon,
tblAssets.IPAddress,
tblAssets.Lastseen,
tblAssets.Lasttried,
tblUSBDevices.Name,
tblUSBDevices.Manufacturer
From tblAssets
Inner Join tblAssetCustom On tblAssets.AssetID = tblAssetCustom.AssetID
Inner Join tsysAssetTypes On tsysAssetTypes.AssetType = tblAssets.Assettype
Inner Join tblUSBDevices On tblAssets.AssetID = tblUSBDevices.AssetID
Where
tblAssetCustom.State = 1
AND tblUSBDevices.Name NOT LIKE '%mouse%'
AND tblUSBDevices.Name NOT LIKE '%keyboard%'